2 Creating and Configuring an Oracle Database

After you plan your database, you can create the database with a graphical tool or a SQL command.

See Also:

  • Using Oracle Managed Files for information about creating a database whose underlying operating system files are automatically created and managed by the Oracle Database server

  • Your platform-specific Oracle Real Application Clusters (Oracle RAC) installation guide for information about creating a database in an Oracle RAC environment

2.1 About Creating an Oracle Database

You typically create a database during Oracle Database software installation. However, you can also create a database after installation.

Reasons to create a database after installation are as follows:

  • You used Oracle Universal Installer (OUI) to install software only, and did not create a database.

  • You want to create another database (and database instance) on the same host computer as an existing Oracle database. In this case, this chapter assumes that the new database uses the same Oracle home as the existing database. You can also create the database in a new Oracle home by running OUI again.

  • You want to make a copy of (clone) a database.

The specific methods for creating a database are:

2.2 Considerations Before Creating the Database

Database creation prepares several operating system files to work together as an Oracle Database. You only need to create a database once, regardless of how many data files it has or how many instances access it. You can create a database to erase information in an existing database and create a new database with the same name and physical structure.

2.2.1 Planning for Database Creation

Prepare to create the database by research and careful planning.

Table 2-1 lists some recommended actions:

Table 2-1 Database Planning Tasks

Action Additional Information

Plan the database tables and indexes and estimate the amount of space they will require.

Oracle Database Structure and Storage

Schema Objects

Plan the layout of the underlying operating system files your database will comprise. Proper distribution of files can improve database performance dramatically by distributing the I/O during file access. You can distribute I/O in several ways when you install Oracle software and create your database. For example, you can place redo log files on separate disks or use striping. You can situate data files to reduce contention. And you can control data density (number of rows to a data block). If you create a Fast Recovery Area, Oracle recommends that you place it on a storage device that is different from that of the data files.

To greatly simplify this planning task, consider using Oracle Managed Files and Automatic Storage Management to create and manage the operating system files that comprise your database storage.

Using Oracle Managed Files

Oracle Automatic Storage Management Administrator's Guide

Oracle Database Performance Tuning Guide

Your Oracle operating system–specific documentation, including the appropriate Oracle Database installation guide.

Select the global database name, which is the name and location of the database within the network structure. Create the global database name by setting both the DB_NAME and DB_DOMAIN initialization parameters.

"Determining the Global Database Name"

Familiarize yourself with the initialization parameters contained in the initialization parameter file. Become familiar with the concept and operation of a server parameter file. A server parameter file lets you store and manage your initialization parameters persistently in a server-side disk file.

"About Initialization Parameters and Initialization Parameter Files"

"What Is a Server Parameter File?"

Oracle Database Reference

Select the database character set.

All character data, including data in the data dictionary, is stored in the database character set. You specify the database character set when you create the database.

See "About Selecting a Character Set" for details.

Oracle Database Globalization Support Guide

Consider which time zones your database must support.

Oracle Database uses one of two time zone files as the source of valid time zones. The default time zone file is timezlrg_11.dat. It contains more time zones than the smaller time zone file, timezone_11.dat.

"Specifying the Database Time Zone File"

Select the standard database block size. This is specified at database creation by the DB_BLOCK_SIZE initialization parameter and cannot be changed after the database is created.

The SYSTEM tablespace and most other tablespaces use the standard block size. Additionally, you can specify up to four nonstandard block sizes when creating tablespaces.

"Specifying Database Block Sizes"

If you plan to store online redo log files on disks with a 4K byte sector size, determine whether you must manually specify redo log block size.

"Planning the Block Size of Redo Log Files"

Determine the appropriate initial sizing for the SYSAUX tablespace.

"About the SYSAUX Tablespace"

Plan to use a default tablespace for non-SYSTEM users to prevent inadvertently saving database objects in the SYSTEM tablespace.

"Creating a Default Permanent Tablespace"

Plan to use an undo tablespace to manage your undo data.

Managing Undo

Develop a backup and recovery strategy to protect the database from failure. It is important to protect the control file by multiplexing, to choose the appropriate backup mode, and to manage the online redo log and archived redo log files.

Managing the Redo Log

Managing Archived Redo Log Files

Managing Control Files

Oracle Database Backup and Recovery User's Guide

Familiarize yourself with the principles and options of starting up and shutting down an instance and mounting and opening a database.

Starting Up and Shutting Down

2.2.2 About Selecting a Character Set

It is important to select the right character set for your database. Oracle recommends AL32UTF8 as the database character set.

AL32UTF8 is Oracle's name for the UTF-8 encoding of the Unicode standard. The Unicode standard is the universal character set that supports most of the currently spoken languages of the world. The use of the Unicode standard is indispensable for any multilingual technology, including database processing.

After a database is created and accumulates production data, changing the database character set is a time consuming and complex project. Therefore, it is very important to select the right character set at installation time. Even if the database does not currently store multilingual data but is expected to store multilingual data within a few years, the choice of AL32UTF8 for the database character set is usually the only good decision. The universality and flexibility of Unicode typically outweighs some additional cost associated with it, such as slightly slower text processing compared to single-byte character sets and higher storage space requirements for non-ASCII text compared to non-Unicode character sets.

If you do not want to use AL32UTF8, and you are not restricted in your choice by a vendor requirement, then Oracle suggests that you use one of the character sets listed as recommended for the database. The recommended character sets were selected based on the requirements of modern client operating systems. Oracle Universal Installer (OUI) presents the recommended list only, and Database Configuration Assistant (DBCA) must be used separately to choose a non-recommended character set. In addition, the default database creation configuration in DBCA allows the selection of the recommended character sets only. You must use the advanced configuration mode of DBCA or the CREATE DATABASE statement to select a non-recommended character set.

Caution:

Do not use the character set named UTF8 as the database character set unless required for compatibility with Oracle Database clients and servers in Oracle8i Release 1 (8.1.7) and earlier, or unless explicitly requested by your application vendor. Despite having a very similar name, UTF8 is not a proper implementation of the Unicode encoding UTF-8. If the UTF8 character set is used where UTF-8 processing is expected, data loss and security issues may occur. This is especially true for Web related data, such as XML and URL addresses.

Note:

You can only select an ASCII-based character set for the database on an ASCII-based platform.

See Also:

Oracle Database Globalization Support Guide for information about the character sets recommended for the database

2.2.3 Meeting Creation Prerequisites

Prerequisites must be met before creating a database.

Before you can create a new database, the following prerequisites must be met:

  • The desired Oracle software must be installed. This includes setting various environment variables unique to your operating system and establishing the directory structure for software and database files.

  • Sufficient memory must be available to start the Oracle Database instance.

  • Sufficient disk storage space must be available for the planned database on the computer that runs Oracle Database.

All of these are discussed in the Oracle Database Installation Guide specific to your operating system. If you use the Oracle Universal Installer, it will guide you through your installation and provide help in setting environment variables and establishing directory structure and authorizations.

2.3 Creating a Database with DBCA

Oracle Database Configuration Assistant (DBCA) is a tool for creating and configuring an Oracle database.

2.3.1 About Creating a Database with DBCA

Oracle strongly recommends using the Database Configuration Assistant (DBCA) to create a database, because it is a more automated approach, and your database is ready to use when DBCA completes.

DBCA can be launched by the Oracle Universal Installer (OUI), depending upon the type of install that you select. You can also launch DBCA as a standalone tool at any time after Oracle Database installation.

You can run DBCA in interactive mode or noninteractive/silent mode. Interactive mode provides a graphical interface and guided workflow for creating and configuring a database. Noninteractive/silent mode enables you to script database creation. You can run DBCA in noninteractive/silent mode by specifying command-line arguments, a response file, or both.

2.3.2 About Creating a Database with Interactive DBCA

The easiest way to create a database is with Database Configuration Assistant (DBCA).

See Oracle Database 2 Day DBA for detailed information about creating a database interactively with DBCA.

2.3.3 About Creating a Database with Noninteractive/Silent DBCA

You can create a database using the noninteractive/silent mode of Database Configuration Assistant (DBCA).

See the following documentation for details on using the noninteractive/silent mode of DBCA:

2.3.3.1 DBCA Examples

Examples illustrate how to create a database with noninteractive/silent mode of Database Configuration Assistant (DBCA).

The following example creates a database by passing command-line arguments to DBCA:

dbca -silent -createDatabase -templateName General_Purpose.dbc
  -gdbname oradb.example.com -sid oradb -responseFile NO_VALUE 
  -characterSet AL32UTF8 -memoryPercentage 30 -emConfiguration LOCAL

Enter SYSTEM user password:
password
Enter SYS user password:
password
Copying database files
1% complete
3% complete
...

To ensure completely silent operation, you can redirect stdout to a file. If you do this, however, you must supply passwords for the administrative accounts in command-line arguments or the response file.

To view brief help for DBCA command-line arguments, enter the following command:

dbca -help

For more detailed argument information, including defaults, view the response file template found on your distribution media. Appendix A of your platform installation guide provides the name and location of this file.

2.4 Creating a Database with the CREATE DATABASE Statement

Using the CREATE DATABASE SQL statement is a more manual approach to creating a database than using Oracle Database Configuration Assistant (DBCA). One advantage of using this statement over using DBCA is that you can create databases from within scripts.

2.4.1 About Creating a Database with the CREATE DATABASE Statement

When you use the CREATE DATABASE statement, you must complete additional actions before you have an operational database. These actions include building views on the data dictionary tables and installing standard PL/SQL packages. You perform these actions by running the supplied scripts.

If you have existing scripts for creating your database, then consider editing those scripts to take advantage of new Oracle Database features.

The instructions in this section apply to single-instance installations only. See the Oracle Real Application Clusters (Oracle RAC) installation guide for your platform for instructions for creating an Oracle RAC database.

Note:

Single-instance does not mean that only one Oracle instance can reside on a single host computer. In fact, multiple Oracle instances (and their associated databases) can run on a single host computer. A single-instance database is a database that is accessed by only one Oracle instance at a time, as opposed to an Oracle RAC database, which is accessed concurrently by multiple Oracle instances on multiple nodes. See Oracle Real Application Clusters Administration and Deployment Guide for more information on Oracle RAC.

Tip:

If you are using Oracle Automatic Storage Management (Oracle ASM) to manage your disk storage, then you must start the Oracle ASM instance and configure your disk groups before performing these steps. See Oracle Automatic Storage Management Administrator's Guide.

2.4.2 Step 1: Specify an Instance Identifier (SID)

The ORACLE_SID environment variable is used to distinguish this instance from other Oracle Database instances that you may create later and run concurrently on the same host computer.

  1. Decide on a unique Oracle system identifier (SID) for your instance.

  2. Open a command window.

    Note:

    Use this command window for the subsequent steps.
  3. Set the ORACLE_SID environment variable.

Restrictions related to the valid characters in an ORACLE_SID are platform-specific. On some platforms, the SID is case-sensitive.

Note:

It is common practice to set the SID to be equal to the database name. The maximum number of characters for the database name is eight. For more information, see the discussion of the DB_NAME initialization parameter in Oracle Database Reference.

The following example for UNIX and Linux operating systems sets the SID for the instance that you will connect to in Step 6: Connect to the Instance:

  • Bourne, Bash, or Korn shell:

    ORACLE_SID=mynewdb
    export ORACLE_SID
    
  • C shell:

    setenv ORACLE_SID mynewdb
    

The following example sets the SID for the Windows operating system:

set ORACLE_SID=mynewdb

See Also:

Oracle Database Concepts for background information about the Oracle instance

2.4.3 Step 2: Ensure That the Required Environment Variables Are Set

Depending on your platform, before you can start SQL*Plus (as required in a later step), you may have to set environment variables, or at least verify that they are set properly.

  • Set required environment variables.

For example, on most platforms, ORACLE_SID and ORACLE_HOME must be set. In addition, it is advisable to set the PATH variable to include the ORACLE_HOME/bin directory. On the UNIX and Linux platforms, you must set these environment variables manually. On the Windows platform, OUI automatically assigns values to ORACLE_HOME and ORACLE_SID in the Windows registry. If you did not create a database upon installation, OUI does not set ORACLE_SID in the registry, and you will have to set the ORACLE_SID environment variable when you create your database later.

2.4.4 Step 3: Choose a Database Administrator Authentication Method

You must be authenticated and granted appropriate system privileges in order to create a database.

  • Decide on an authentication method.

You can be authenticated as an administrator with the required privileges in the following ways:

  • With a password file

  • With operating system authentication

To be authenticated with a password file, create the password file as described in "Creating and Maintaining a Database Password File". To be authenticated with operating system authentication, ensure that you log in to the host computer with a user account that is a member of the appropriate operating system user group. On the UNIX and Linux platforms, for example, this is typically the dba user group. On the Windows platform, the user installing the Oracle software is automatically placed in the required user group.

See Also:

2.4.5 Step 4: Create the Initialization Parameter File

When an Oracle instance starts, it reads an initialization parameter file. This file can be a text file, which can be created and modified with a text editor, or a binary file, which is created and dynamically modified by the database. The binary file, which is preferred, is called a server parameter file. In this step, you create a text initialization parameter file. In a later step, you create a server parameter file from the text file.

  • Create the initialization parameter file.

One way to create the text initialization parameter file is to edit the sample presented in "Sample Initialization Parameter File".

If you create the initialization parameter file manually, ensure that it contains at least the parameters listed in Table 2-2. All other parameters not listed have default values.

Table 2-2 Recommended Minimum Initialization Parameters

Parameter Name Mandatory Notes

DB_NAME

Yes

Database identifier. Must correspond to the value used in the CREATE DATABASE statement. Maximum 8 characters.

CONTROL_FILES

No

Strongly recommended. If not provided, then the database instance creates one control file in the same location as the initialization parameter file. Providing this parameter enables you to multiplex control files. See "Creating Initial Control Files" for more information.

MEMORY_TARGET

No

Sets the total amount of memory used by the instance and enables automatic memory management. You can choose other initialization parameters instead of this one for more manual control of memory usage. See "Configuring Memory Manually".

For convenience, store your initialization parameter file in the Oracle Database default location, using the default file name. Then when you start your database, it will not be necessary to specify the PFILE clause of the STARTUP command, because Oracle Database automatically looks in the default location for the initialization parameter file.

For more information about initialization parameters and the initialization parameter file, including the default name and location of the initialization parameter file for your platform, see "About Initialization Parameters and Initialization Parameter Files".

See Also:

2.4.6 Step 5: (Windows Only) Create an Instance

On the Windows platform, before you can connect to an instance, you must manually create it if it does not already exist. The ORADIM command creates an Oracle Database instance by creating a new Windows service.

To create an instance:

  • Enter the following command at a Windows command prompt:

    oradim -NEW -SID sid -STARTMODE MANUAL -PFILE file
    

    Replace the following placeholders with appropriate values:

    • sid - The desired SID (for example mynewdb)

    • file - The full path to the text initialization parameter file

Caution:

Do not set the -STARTMODE argument to AUTO at this point, because this causes the new instance to start and attempt to mount the database, which does not exist yet. You can change this parameter to AUTO, if desired, in Step 14: (Optional) Enable Automatic Instance Startup.

Most Oracle Database services log on to the system using the privileges of the Oracle Home User. The service runs with the privileges of this user. The ORADIM command prompts you for the password to this user account. You can specify other options using ORADIM.

See Also:

2.4.7 Step 6: Connect to the Instance

Start SQL*Plus and connect to your Oracle Database instance with the SYSDBA administrative privilege.

  • To authenticate with a password file, enter the following commands, and then enter the SYS password when prompted:

    $ sqlplus /nolog
    SQL> CONNECT SYS AS SYSDBA
    
  • To authenticate with operating system authentication, enter the following commands:

    $ sqlplus /nolog
    SQL> CONNECT / AS SYSDBA
    

SQL*Plus outputs the following message:

Connected to an idle instance.

Note:

SQL*Plus may output a message similar to the following:

Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

If so, the instance is already started. You may have connected to the wrong instance. Exit SQL*Plus with the EXIT command, check that ORACLE_SID is set properly, and repeat this step.

2.4.8 Step 7: Create a Server Parameter File

The server parameter file enables you to change initialization parameters with the ALTER SYSTEM command and persist the changes across a database shutdown and startup. You create the server parameter file from your edited text initialization file.

  • Run the following SQL*Plus command:
    CREATE SPFILE FROM PFILE;
    

This SQL*Plus command reads the text initialization parameter file (PFILE) with the default name from the default location, creates a server parameter file (SPFILE) from the text initialization parameter file, and writes the SPFILE to the default location with the default SPFILE name.

You can also supply the file name and path for both the PFILE and SPFILE if you are not using default names and locations.

Tip:

The database must be restarted before the server parameter file takes effect.

Note:

Although creating a server parameter file is optional at this point, it is recommended. If you do not create a server parameter file, the instance continues to read the text initialization parameter file whenever it starts.

Important—If you are using Oracle Managed Files and your initialization parameter file does not contain the CONTROL_FILES parameter, then you must create a server parameter file now so the database can save the names and locations of the control files that it creates during the CREATE DATABASE statement. See "Specifying Oracle Managed Files at Database Creation" for more information.

2.4.9 Step 8: Start the Instance

Start an instance without mounting a database.

  • Run the STARTUP command with the NOMOUNT clause.

Typically, you do this only during database creation or while performing maintenance on the database. In this example, because the initialization parameter file or server parameter file is stored in the default location, you are not required to specify the PFILE clause:

STARTUP NOMOUNT

At this point, the instance memory is allocated and its processes are started. The database itself does not yet exist.

See Also:

2.4.10 Step 9: Issue the CREATE DATABASE Statement

To create the new database, use the CREATE DATABASE statement.

  • Run the CREATE DATABASE statement.

Note:

If you are creating a multitenant container database (CDB), then see the examples in "Creating a CDB with the CREATE DATABASE Statement".

Example 1

The following statement creates a database mynewdb. This database name must agree with the DB_NAME parameter in the initialization parameter file. This example assumes the following:

  • The initialization parameter file specifies the number and location of control files with the CONTROL_FILES parameter.

  • The directory /u01/app/oracle/oradata/mynewdb exists.

  • The directories /u01/logs/my and /u02/logs/my exist.

CREATE DATABASE mynewdb
   USER SYS IDENTIFIED BY sys_password
   USER SYSTEM IDENTIFIED BY system_password
   LOGFILE GROUP 1 ('/u01/logs/my/redo01a.log','/u02/logs/my/redo01b.log') SIZE 100M BLOCKSIZE 512,
           GROUP 2 ('/u01/logs/my/redo02a.log','/u02/logs/my/redo02b.log') SIZE 100M BLOCKSIZE 512,
           GROUP 3 ('/u01/logs/my/redo03a.log','/u02/logs/my/redo03b.log') SIZE 100M BLOCKSIZE 512
   MAXLOGHISTORY 1
   MAXLOGFILES 16
   MAXLOGMEMBERS 3
   MAXDATAFILES 1024
   CHARACTER SET AL32UTF8
   NATIONAL CHARACTER SET AL16UTF16
   EXTENT MANAGEMENT LOCAL
   DATAFILE '/u01/app/oracle/oradata/mynewdb/system01.dbf'
     SIZE 700M REUSE AUTOEXTEND ON NEXT 10240K MAXSIZE UNLIMITED
   SYSAUX DATAFILE '/u01/app/oracle/oradata/mynewdb/sysaux01.dbf'
     SIZE 550M REUSE AUTOEXTEND ON NEXT 10240K MAXSIZE UNLIMITED
   DEFAULT TABLESPACE users
      DATAFILE '/u01/app/oracle/oradata/mynewdb/users01.dbf'
      SIZE 500M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED
   DEFAULT TEMPORARY TABLESPACE tempts1
      TEMPFILE '/u01/app/oracle/oradata/mynewdb/temp01.dbf'
      SIZE 20M REUSE AUTOEXTEND ON NEXT 640K MAXSIZE UNLIMITED
   UNDO TABLESPACE undotbs1
      DATAFILE '/u01/app/oracle/oradata/mynewdb/undotbs01.dbf'
      SIZE 200M REUSE AUTOEXTEND ON NEXT 5120K MAXSIZE UNLIMITED
   USER_DATA TABLESPACE usertbs
      DATAFILE '/u01/app/oracle/oradata/mynewdb/usertbs01.dbf'
      SIZE 200M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED;

A database is created with the following characteristics:

  • The database is named mynewdb. Its global database name is mynewdb.us.example.com, where the domain portion (us.example.com) is taken from the initialization parameter file. See "Determining the Global Database Name".

  • Three control files are created as specified by the CONTROL_FILES initialization parameter, which was set before database creation in the initialization parameter file. See "Sample Initialization Parameter File" and "Specifying Control Files ".

  • The passwords for user accounts SYS and SYSTEM are set to the values that you specified. The passwords are case-sensitive. The two clauses that specify the passwords for SYS and SYSTEM are not mandatory in this release of Oracle Database. However, if you specify either clause, then you must specify both clauses. For further information about the use of these clauses, see "Protecting Your Database: Specifying Passwords for Users SYS and SYSTEM".

  • The new database has three redo log file groups, each with two members, as specified in the LOGFILE clause. MAXLOGFILES, MAXLOGMEMBERS, and MAXLOGHISTORY define limits for the redo log. See "Choosing the Number of Redo Log Files". The block size for the redo log files is set to 512 bytes, the same size as physical sectors on disk. The BLOCKSIZE clause is optional if block size is to be the same as physical sector size (the default). Typical sector size and thus typical block size is 512. Permissible values for BLOCKSIZE are 512, 1024, and 4096. For newer disks with a 4K sector size, optionally specify BLOCKSIZE as 4096. See "Planning the Block Size of Redo Log Files" for more information.

  • MAXDATAFILES specifies the maximum number of data files that can be open in the database. This number affects the initial sizing of the control file.

    Note:

    You can set several limits during database creation. Some of these limits are limited by and affected by operating system limits. For example, if you set MAXDATAFILES, Oracle Database allocates enough space in the control file to store MAXDATAFILES file names, even if the database has only one data file initially. However, because the maximum control file size is limited and operating system dependent, you might not be able to set all CREATE DATABASE parameters at their theoretical maximums.

    For more information about setting limits during database creation, see the Oracle Database SQL Language Reference and your operating system–specific Oracle documentation.

  • The AL32UTF8 character set is used to store data in this database.

  • The AL16UTF16 character set is specified as the NATIONAL CHARACTER SET used to store data in columns specifically defined as NCHAR, NCLOB, or NVARCHAR2.

  • The SYSTEM tablespace, consisting of the operating system file /u01/app/oracle/oradata/mynewdb/system01.dbf, is created as specified by the DATAFILE clause. If a file with that name already exists, then it is overwritten.

  • The SYSTEM tablespace is created as a locally managed tablespace. See "Creating a Locally Managed SYSTEM Tablespace".

  • A SYSAUX tablespace is created, consisting of the operating system file /u01/app/oracle/oradata/mynewdb/sysaux01.dbf as specified in the SYSAUX DATAFILE clause. See "About the SYSAUX Tablespace".

  • The DEFAULT TABLESPACE clause creates and names a default permanent tablespace for this database.

  • The DEFAULT TEMPORARY TABLESPACE clause creates and names a default temporary tablespace for this database. See "Creating a Default Temporary Tablespace".

  • The UNDO TABLESPACE clause creates and names an undo tablespace that is used to store undo data for this database if you have specified UNDO_MANAGEMENT=AUTO in the initialization parameter file. If you omit this parameter, then it defaults to AUTO. See "Using Automatic Undo Management: Creating an Undo Tablespace".

  • The USER_DATA TABLESPACE clause creates and names the tablespace for storing user data and database options such as Oracle XML DB.

  • Online redo logs will not initially be archived, because the ARCHIVELOG clause is not specified in this CREATE DATABASE statement. This is customary during database creation. You can later use an ALTER DATABASE statement to switch to ARCHIVELOG mode. The initialization parameters in the initialization parameter file for mynewdb relating to archiving are LOG_ARCHIVE_DEST_1 and LOG_ARCHIVE_FORMAT. See Managing Archived Redo Log Files.

Tips:

  • Ensure that all directories used in the CREATE DATABASE statement exist. The CREATE DATABASE statement does not create directories.

  • If you are not using Oracle Managed Files, then every tablespace clause must include a DATAFILE or TEMPFILE clause.

  • If database creation fails, then you can look at the alert log to determine the reason for the failure and to determine corrective actions. See "Viewing the Alert Log". If you receive an error message that contains a process number, then examine the trace file for that process. Look for the trace file that contains the process number in the trace file name. See "Finding Trace Files" for more information.

  • To resubmit the CREATE DATABASE statement after a failure, you must first shut down the instance and delete any files created by the previous CREATE DATABASE statement.

Example 2

This example illustrates creating a database with Oracle Managed Files, which enables you to use a much simpler CREATE DATABASE statement. To use Oracle Managed Files, the initialization parameter DB_CREATE_FILE_DEST must be set. This parameter defines the base directory for the various database files that the database creates and automatically names. The following statement is an example of setting this parameter in the initialization parameter file:

DB_CREATE_FILE_DEST='/u01/app/oracle/oradata'

With Oracle Managed Files and the following CREATE DATABASE statement, the database creates the SYSTEM and SYSAUX tablespaces, creates the additional tablespaces specified in the statement, and chooses default sizes and properties for all data files, control files, and redo log files. Note that these properties and the other default database properties set by this method may not be suitable for your production environment, so it is recommended that you examine the resulting configuration and modify it if necessary.

CREATE DATABASE mynewdb
USER SYS IDENTIFIED BY sys_password
USER SYSTEM IDENTIFIED BY system_password
EXTENT MANAGEMENT LOCAL
DEFAULT TEMPORARY TABLESPACE temp
UNDO TABLESPACE undotbs1
DEFAULT TABLESPACE users;

Tip:

If your CREATE DATABASE statement fails, and if you did not complete Step 7, then ensure that there is not a pre-existing server parameter file (SPFILE) for this instance that is setting initialization parameters in an unexpected way. For example, an SPFILE contains a setting for the complete path to all control files, and the CREATE DATABASE statement fails if those control files do not exist. Ensure that you shut down and restart the instance (with STARTUP NOMOUNT) after removing an unwanted SPFILE. See "Managing Initialization Parameters Using a Server Parameter File" for more information.

See Also:

2.4.11 Step 10: Create Additional Tablespaces

To make the database functional, you must create additional tablespaces for your application data.

  • Run the CREATE TABLESPACE statement to create additional tablespaces.

The following sample script creates some additional tablespaces:

CREATE TABLESPACE apps_tbs LOGGING 
     DATAFILE '/u01/app/oracle/oradata/mynewdb/apps01.dbf' 
     SIZE 500M REUSE AUTOEXTEND ON NEXT  1280K MAXSIZE UNLIMITED 
     EXTENT MANAGEMENT LOCAL;
-- create a tablespace for indexes, separate from user tablespace (optional)
CREATE TABLESPACE indx_tbs LOGGING 
     DATAFILE '/u01/app/oracle/oradata/mynewdb/indx01.dbf' 
     SIZE 100M REUSE AUTOEXTEND ON NEXT  1280K MAXSIZE UNLIMITED 
     EXTENT MANAGEMENT LOCAL;

For information about creating tablespaces, see Managing Tablespaces.

2.4.12 Step 11: Run Scripts to Build Data Dictionary Views

Run the scripts necessary to build data dictionary views, synonyms, and PL/SQL packages, and to support proper functioning of SQL*Plus.

  1. In SQL*Plus, connect to your Oracle Database instance with the SYSDBA administrative privilege:
    @?/rdbms/admin/catalog.sql
    @?/rdbms/admin/catproc.sql
    @?/rdbms/admin/utlrp.sql
    
  2. In SQL*Plus, connect to your Oracle Database instance as SYSTEM user:
    @?/sqlplus/admin/pupbld.sql
    

The at-sign (@) is shorthand for the command that runs a SQL*Plus script. The question mark (?) is a SQL*Plus variable indicating the Oracle home directory. The following table contains descriptions of the scripts:

Script Description

catalog.sql

Creates the views of the data dictionary tables, the dynamic performance views, and public synonyms for many of the views. Grants PUBLIC access to the synonyms.

catproc.sql

Runs all scripts required for or used with PL/SQL.

utlrp.sql

Recompiles all PL/SQL modules that are in an invalid state, including packages, procedures, and types.

pupbld.sql

Required for SQL*Plus. Enables SQL*Plus to disable commands by user.

2.4.13 Step 12: (Optional) Run Scripts to Install Additional Options

You may want to run other scripts. The scripts that you run are determined by the features and options you choose to use or install.

  • Run scripts to install additional options.

Many of the scripts available to you are described in the Oracle Database Reference.

If you plan to install other Oracle products to work with this database, then see the installation instructions for those products. Some products require you to create additional data dictionary tables. Usually, command files are provided to create and load these tables into the database data dictionary.

See your Oracle documentation for the specific products that you plan to install for installation and administration instructions.

2.4.14 Step 13: Back Up the Database

Take a full backup of the database to ensure that you have a complete set of files from which to recover if a media failure occurs.

  • Back up the database.

For information on backing up a database, see Oracle Database Backup and Recovery User's Guide.

2.4.15 Step 14: (Optional) Enable Automatic Instance Startup

You might want to configure the Oracle instance to start automatically when its host computer restarts.

  • Configure the Oracle instance to start automatically when its host computer restarts.

See your operating system documentation for instructions. For example, on Windows, use the following command to configure the database service to start the instance upon computer restart:

ORADIM -EDIT -SID sid -STARTMODE AUTO -SRVCSTART SYSTEM [-SPFILE]

You must use the -SPFILE argument if you want the instance to read an SPFILE upon automatic restart.

2.5 Specifying CREATE DATABASE Statement Clauses

When you execute a CREATE DATABASE statement, Oracle Database performs several operations. The actual operations performed depend on the clauses that you specify in the CREATE DATABASE statement and the initialization parameters that you have set.

2.5.1 About CREATE DATABASE Statement Clauses

You can use the CREATE DATABASE clauses to simplify the creation and management of your database.

When you execute a CREATE DATABASE statement, Oracle Database performs at least these operations:

  • Creates the data files for the database

  • Creates the control files for the database

  • Creates the online redo logs for the database and establishes the ARCHIVELOG mode

  • Creates the SYSTEM tablespace

  • Creates the SYSAUX tablespace

  • Creates the data dictionary

  • Sets the character set that stores data in the database

  • Sets the database time zone

  • Mounts and opens the database for use

2.5.2 Protecting Your Database: Specifying Passwords for Users SYS and SYSTEM

To protect your database, specify passwords for users SYS and SYSTEM.

  • In the CREATE DATABASE statement, include clauses that specify the password for users SYS and SYSTEM.

The clauses of the CREATE DATABASE statement used for specifying the passwords for users SYS and SYSTEM are:

  • USER SYS IDENTIFIED BY password

  • USER SYSTEM IDENTIFIED BY password

If you omit these clauses, then these users are assigned the default passwords change_on_install and manager, respectively. A record is written to the alert log indicating that the default passwords were used. To protect your database, you must change these passwords using the ALTER USER statement immediately after database creation.

Oracle strongly recommends that you specify these clauses, even though they are optional in this release of Oracle Database. The default passwords are commonly known, and if you neglect to change them later, then you leave database vulnerable to attack by malicious users.

When choosing a password, keep in mind that passwords are case-sensitive. Also, there may be password formatting requirements for your database. See the section entitled "How Oracle Database Checks the Complexity of Passwords" in Oracle Database Security Guide for more information.

2.5.3 Creating a Locally Managed SYSTEM Tablespace

During database creation, create a locally managed SYSTEM tablespace. A locally managed tablespace uses a bitmap stored in each data file to manage the extents.

  • Specify the EXTENT MANAGEMENT LOCAL clause in the CREATE DATABASE statement to create a locally managed SYSTEM tablespace.

If you do not specify the EXTENT MANAGEMENT LOCAL clause, then by default the database creates a dictionary-managed SYSTEM tablespace. Dictionary-managed tablespaces are deprecated.

If you create your database with a locally managed SYSTEM tablespace, and if you are not using Oracle Managed Files, then ensure that the following conditions are met:

  • You specify the DEFAULT TEMPORARY TABLESPACE clause in the CREATE DATABASE statement.

  • You include the UNDO TABLESPACE clause in the CREATE DATABASE statement.

See Also:

2.5.4 Specify Data File Attributes for the SYSAUX Tablespace

The SYSAUX tablespace is created by default, but you can specify its data file attributes during database creation.

To specify data file attributes for the SYSAUX tablespace:

  • Include the SYSAUX DATAFILE clause in the CREATE DATABASE statement.

If you include a DATAFILE clause for the SYSTEM tablespace, then you must specify the SYSAUX DATAFILE clause as well, or the CREATE DATABASE statement will fail. This requirement does not exist if the Oracle Managed Files feature is enabled (see "Specifying Oracle Managed Files at Database Creation").

2.5.4.1 About the SYSAUX Tablespace

The SYSAUX tablespace is always created at database creation. The SYSAUX tablespace serves as an auxiliary tablespace to the SYSTEM tablespace. Because it is the default tablespace for many Oracle Database features and products that previously required their own tablespaces, it reduces the number of tablespaces required by the database. It also reduces the load on the SYSTEM tablespace.

You can specify only data file attributes for the SYSAUX tablespace, using the SYSAUX DATAFILE clause in the CREATE DATABASE statement. Mandatory attributes of the SYSAUX tablespace are set by Oracle Database and include:

  • PERMANENT

  • READ WRITE

  • EXTENT MANAGMENT LOCAL

  • SEGMENT SPACE MANAGMENT AUTO

You cannot alter these attributes with an ALTER TABLESPACE statement, and any attempt to do so will result in an error. You cannot drop or rename the SYSAUX tablespace.

The size of the SYSAUX tablespace is determined by the size of the database components that occupy SYSAUX. You can view a list of these components by querying the V$SYSAUX_OCCUPANTS view. Based on the initial sizes of these components, the SYSAUX tablespace must be at least 400 MB at the time of database creation. The space requirements of the SYSAUX tablespace will increase after the database is fully deployed, depending on the nature of its use and workload. For more information on how to manage the space consumption of the SYSAUX tablespace on an ongoing basis, see the "Managing the SYSAUX Tablespace".

The SYSAUX tablespace has the same security attributes as the SYSTEM tablespace.

2.5.5 Using Automatic Undo Management: Creating an Undo Tablespace

Automatic undo management uses an undo tablespace.

  • To enable automatic undo management, set the UNDO_MANAGEMENT initialization parameter to AUTO in your initialization parameter file. Or, omit this parameter, and the database defaults to automatic undo management.

In this mode, undo data is stored in an undo tablespace and is managed by Oracle Database. To define and name the undo tablespace yourself, you must include the UNDO TABLESPACE clause in the CREATE DATABASE statement at database creation time. If you omit this clause, and automatic undo management is enabled, then the database creates a default undo tablespace named SYS_UNDOTBS.

Note:

If you decide to define the undo tablespace yourself, then ensure that its block size matches the highest data file block size for the database.

See Also:

2.5.6 Creating a Default Permanent Tablespace

Oracle strongly recommends that you create a default permanent tablespace. Oracle Database assigns to this tablespace any non-SYSTEM users for whom you do not explicitly specify a different permanent tablespace.

To specify a default permanent tablespace for the database:

  • Include the DEFAULT TABLESPACE clause in the CREATE DATABASE statement

If you do not specify the DEFAULT TABLESPACE clause, then the SYSTEM tablespace is the default permanent tablespace for non-SYSTEM users.

See Also:

Oracle Database SQL Language Reference for the syntax of the DEFAULT TABLESPACE clause of CREATE DATABASE and ALTER DATABASE

2.5.7 Creating a Default Temporary Tablespace

When you create a default temporary tablespace, Oracle Database assigns it as the temporary tablespace for users who are not explicitly assigned a temporary tablespace.

To create a default temporary tablespace for the database:

  • Include the DEFAULT TEMPORARY TABLESPACE clause in the CREATE DATABASE statement.

You can explicitly assign a temporary tablespace or tablespace group to a user in the CREATE USER statement. However, if you do not do so, and if no default temporary tablespace has been specified for the database, then by default these users are assigned the SYSTEM tablespace as their temporary tablespace. It is not good practice to store temporary data in the SYSTEM tablespace, and it is cumbersome to assign every user a temporary tablespace individually. Therefore, Oracle recommends that you use the DEFAULT TEMPORARY TABLESPACE clause of CREATE DATABASE.

Note:

When you specify a locally managed SYSTEM tablespace, the SYSTEM tablespace cannot be used as a temporary tablespace. In this case you must create a default temporary tablespace. This behavior is explained in "Creating a Locally Managed SYSTEM Tablespace".

See Also:

2.5.8 Specifying Oracle Managed Files at Database Creation

You can minimize the number of clauses and parameters that you specify in your CREATE DATABASE statement by using the Oracle Managed Files feature.

  • Specify either a directory or Oracle Automatic Storage Management (Oracle ASM) disk group in which your files are created and managed by Oracle Database.

By including any of the initialization parameters DB_CREATE_FILE_DEST, DB_CREATE_ONLINE_LOG_DEST_n, or DB_RECOVERY_FILE_DEST in your initialization parameter file, you instruct Oracle Database to create and manage the underlying operating system files of your database. Oracle Database will automatically create and manage the operating system files for the following database structures, depending on which initialization parameters you specify and how you specify clauses in your CREATE DATABASE statement:

  • Tablespaces and their data files

  • Temporary tablespaces and their temp files

  • Control files

  • Online redo logs

  • Archived redo log files

  • Flashback logs

  • Block change tracking files

  • RMAN backups

See Also:

"Specifying a Fast Recovery Area" for information about setting initialization parameters that create a Fast Recovery Area

The following CREATE DATABASE statement shows briefly how the Oracle Managed Files feature works, assuming you have specified required initialization parameters:

CREATE DATABASE mynewdb
     USER SYS IDENTIFIED BY sys_password
     USER SYSTEM IDENTIFIED BY system_password
     EXTENT MANAGEMENT LOCAL
     UNDO TABLESPACE undotbs1
     DEFAULT TEMPORARY TABLESPACE tempts1
     DEFAULT TABLESPACE users;
  • The SYSTEM tablespace is created as a locally managed tablespace. Without the EXTENT MANAGEMENT LOCAL clause, the SYSTEM tablespace is created as dictionary managed, which is not recommended.

  • No DATAFILE clause is specified, so the database creates an Oracle managed data file for the SYSTEM tablespace.

  • No LOGFILE clauses are included, so the database creates two Oracle managed redo log file groups.

  • No SYSAUX DATAFILE is included, so the database creates an Oracle managed data file for the SYSAUX tablespace.

  • No DATAFILE subclause is specified for the UNDO TABLESPACE and DEFAULT TABLESPACE clauses, so the database creates an Oracle managed data file for each of these tablespaces.

  • No TEMPFILE subclause is specified for the DEFAULT TEMPORARY TABLESPACE clause, so the database creates an Oracle managed temp file.

  • If no CONTROL_FILES initialization parameter is specified in the initialization parameter file, then the database also creates an Oracle managed control file.

  • If you are using a server parameter file (see "Managing Initialization Parameters Using a Server Parameter File"), then the database automatically sets the appropriate initialization parameters.

    See Also:

2.5.9 Supporting Bigfile Tablespaces During Database Creation

Oracle Database simplifies management of tablespaces and enables support for extremely large databases by letting you create bigfile tablespaces.

Bigfile tablespaces can contain only one file, but that file can have up to 4G blocks. The maximum number of data files in an Oracle Database is limited (usually to 64K files). Therefore, bigfile tablespaces can significantly enhance the storage capacity of an Oracle Database.

This section discusses the clauses of the CREATE DATABASE statement that let you include support for bigfile tablespaces.

See Also:

"Bigfile Tablespaces" for more information about bigfile tablespaces

2.5.9.1 Specifying the Default Tablespace Type

The SET DEFAULT...TABLESPACE clause of the CREATE DATABASE statement determines the default type of tablespace for this database in subsequent CREATE TABLESPACE statements.

  • Specify either SET DEFAULT BIGFILE TABLESPACE or SET DEFAULT SMALLFILE TABLESPACE.

If you omit this clause, then the default is a smallfile tablespace, which is the traditional type of Oracle Database tablespace. A smallfile tablespace can contain up to 1022 files with up to 4M blocks each.

The use of bigfile tablespaces further enhances the Oracle Managed Files feature, because bigfile tablespaces make data files completely transparent for users. SQL syntax for the ALTER TABLESPACE statement has been extended to allow you to perform operations on tablespaces, rather than the underlying data files.

The CREATE DATABASE statement shown in "Specifying Oracle Managed Files at Database Creation" can be modified as follows to specify that the default type of tablespace is a bigfile tablespace:

CREATE DATABASE mynewdb
     USER SYS IDENTIFIED BY sys_password
     USER SYSTEM IDENTIFIED BY system_password
     SET DEFAULT BIGFILE TABLESPACE
     UNDO TABLESPACE undotbs1
     DEFAULT TEMPORARY TABLESPACE tempts1;

To dynamically change the default tablespace type after database creation, use the SET DEFAULT TABLESPACE clause of the ALTER DATABASE statement:

ALTER DATABASE SET DEFAULT BIGFILE TABLESPACE;

You can determine the current default tablespace type for the database by querying the DATABASE_PROPERTIES data dictionary view as follows:

SELECT PROPERTY_VALUE FROM DATABASE_PROPERTIES 
   WHERE PROPERTY_NAME = 'DEFAULT_TBS_TYPE';

2.5.9.2 Overriding the Default Tablespace Type

The SYSTEM and SYSAUX tablespaces are always created with the default tablespace type. However, you optionally can explicitly override the default tablespace type for the UNDO and DEFAULT TEMPORARY tablespace during the CREATE DATABASE operation.

  • Specify an UNDO TABLESPACE clause or a DEFAULT TEMPORARY TABLESPACE clause that overrides the default tablespace type.

For example, you can create a bigfile UNDO tablespace in a database with the default tablespace type of smallfile as follows:

CREATE DATABASE mynewdb
...
     BIGFILE UNDO TABLESPACE undotbs1
        DATAFILE '/u01/oracle/oradata/mynewdb/undotbs01.dbf'
        SIZE 200M REUSE AUTOEXTEND ON MAXSIZE UNLIMITED;

You can create a smallfile DEFAULT TEMPORARY tablespace in a database with the default tablespace type of bigfile as follows:

CREATE DATABASE mynewdb
   SET DEFAULT BIGFILE TABLESPACE
...
     SMALLFILE DEFAULT TEMPORARY TABLESPACE tempts1
        TEMPFILE '/u01/oracle/oradata/mynewdb/temp01.dbf' 
        SIZE 20M REUSE
...

2.5.10 Specifying the Database Time Zone and Time Zone File

Oracle Database datetime and interval data types and time zone support make it possible to store consistent information about the time of events and transactions.

2.5.10.1 Setting the Database Time Zone

You can set the database time zone with the SET TIME_ZONE clause of the CREATE DATABASE statement.

  • Set the database time zone when the database is created by using the SET TIME_ZONE clause of the CREATE DATABASE statement.

If you do not set the database time zone, then it defaults to the time zone of the host operating system.

You can change the database time zone for a session by using the SET TIME_ZONE clause of the ALTER SESSION statement.

See Also:

Oracle Database Globalization Support Guide for more information about setting the database time zone

2.5.10.2 About the Database Time Zone Files

Two time zone files are included in a subdirectory of the Oracle home directory. The time zone files contain the valid time zone names.

The following information is also included for each time zone:

  • Offset from Coordinated Universal Time (UTC)

  • Transition times for Daylight Saving Time

  • Abbreviations for standard time and Daylight Saving Time

The default time zone file is ORACLE_HOME/oracore/zoneinfo/timezlrg_11.dat. A smaller time zone file with fewer time zones can be found in ORACLE_HOME/oracore/zoneinfo/timezone_11.dat.

To view the time zone names in the file being used by your database, use the following query:

SELECT * FROM V$TIMEZONE_NAMES;

See Also:

Oracle Database Globalization Support Guide for more information about managing and selecting time zone files

2.5.10.3 Specifying the Database Time Zone File

All databases that share information must use the same time zone data file.

The database server always uses the large time zone file by default.

To use the small time zone file on the client and know that all your data will refer only to regions in the small file:

  • Set the ORA_TZFILE environment variable on the client to the full path name of the timezone version.dat file on the client, where version matches the time zone file version that is being used by the database server.

If you are already using the default larger time zone file on the client, then it is not practical to change to the smaller time zone file, because the database may contain data with time zones that are not part of the smaller file.

2.5.11 Specifying FORCE LOGGING Mode

Some data definition language statements (such as CREATE TABLE) allow the NOLOGGING clause, which causes some database operations not to generate redo records in the database redo log. The NOLOGGING setting can speed up operations that can be easily recovered outside of the database recovery mechanisms, but it can negatively affect media recovery and standby databases.

Oracle Database lets you force the writing of redo records even when NOLOGGING has been specified in DDL statements. The database never generates redo records for temporary tablespaces and temporary segments, so forced logging has no affect for objects.

See Also:

Oracle Database SQL Language Reference for information about operations that can be done in NOLOGGING mode

2.5.11.1 Using the FORCE LOGGING Clause

You can force the writing of redo records even when NOLOGGING is specified in DDL statements.

To put the database into FORCE LOGGING mode:

  • Include the FORCE LOGGING clause in the CREATE DATABASE statement.

If you do not specify this clause, then the database is not placed into FORCE LOGGING mode.

Use the ALTER DATABASE statement to place the database into FORCE LOGGING mode after database creation. This statement can take a considerable time for completion, because it waits for all unlogged direct writes to complete.

You can cancel FORCE LOGGING mode using the following SQL statement:

ALTER DATABASE NO FORCE LOGGING;

Independent of specifying FORCE LOGGING for the database, you can selectively specify FORCE LOGGING or NO FORCE LOGGING at the tablespace level. However, if FORCE LOGGING mode is in effect for the database, it takes precedence over the tablespace setting. If it is not in effect for the database, then the individual tablespace settings are enforced. Oracle recommends that either the entire database is placed into FORCE LOGGING mode, or individual tablespaces be placed into FORCE LOGGING mode, but not both.

The FORCE LOGGING mode is a persistent attribute of the database. That is, if the database is shut down and restarted, it remains in the same logging mode. However, if you re-create the control file, the database is not restarted in the FORCE LOGGING mode unless you specify the FORCE LOGGING clause in the CREATE CONTROL FILE statement.

See Also:

"Controlling the Writing of Redo Records" for information about using the FORCE LOGGING clause for tablespace creation.

2.5.11.2 Performance Considerations of FORCE LOGGING Mode

FORCE LOGGING mode results in some performance degradation.

If the primary reason for specifying FORCE LOGGING is to ensure complete media recovery, and there is no standby database active, then consider the following:

  • How many media failures are likely to happen?

  • How serious is the damage if unlogged direct writes cannot be recovered?

  • Is the performance degradation caused by forced logging tolerable?

If the database is running in NOARCHIVELOG mode, then generally there is no benefit to placing the database in FORCE LOGGING mode. Media recovery is not possible in NOARCHIVELOG mode, so if you combine it with FORCE LOGGING, the result may be performance degradation with little benefit.

2.6 Specifying Initialization Parameters

You can add or edit basic initialization parameters before you create your new database.

See Also:

  • Oracle Database Reference for descriptions of all initialization parameters including their default settings

  • Managing Memory for a discussion of the initialization parameters that pertain to memory management

2.6.1 About Initialization Parameters and Initialization Parameter Files

When an Oracle instance starts, it reads initialization parameters from an initialization parameter file. This file must at a minimum specify the DB_NAME parameter. All other parameters have default values.

The initialization parameter file can be either a read-only text file, a PFILE, or a read/write binary file.

The binary file is called a server parameter file. A server parameter file enables you to change initialization parameters with ALTER SYSTEM commands and to persist the changes across a shutdown and startup. It also provides a basis for self-tuning by Oracle Database. For these reasons, it is recommended that you use a server parameter file. You can create one manually from your edited text initialization file, or automatically by using Database Configuration Assistant (DBCA) to create your database.

Before you manually create a server parameter file, you can start an instance with a text initialization parameter file. Upon startup, the Oracle instance first searches for a server parameter file in a default location, and if it does not find one, searches for a text initialization parameter file. You can also override an existing server parameter file by naming a text initialization parameter file as an argument of the STARTUP command.

Default file names and locations for the text initialization parameter file are shown in the following table:

Platform Default Name Default Location

UNIX and Linux

initORACLE_SID.ora

For example, the initialization parameter file for the mynewdb database is named:

initmynewdb.ora

ORACLE_HOME/dbs

Windows

initORACLE_SID.ora

ORACLE_HOME\database

If you are creating an Oracle database for the first time, Oracle suggests that you minimize the number of parameter values that you alter. As you become more familiar with your database and environment, you can dynamically tune many initialization parameters using the ALTER SYSTEM statement. If you are using a text initialization parameter file, then your changes are effective only for the current instance. To make them permanent, you must update them manually in the initialization parameter file, or they will be lost over the next shutdown and startup of the database. If you are using a server parameter file, then initialization parameter file changes made by the ALTER SYSTEM statement can persist across shutdown and startup.

2.6.1.1 Sample Initialization Parameter File

Oracle Database provides generally appropriate values in a sample text initialization parameter file. You can edit these Oracle-supplied initialization parameters and add others, depending upon your configuration and options and how you plan to tune the database.

The sample text initialization parameter file is named init.ora and is found in the following location on most platforms:

ORACLE_HOME/dbs

The following is the content of the sample file:

##############################################################################
# Example INIT.ORA file
#
# This file is provided by Oracle Corporation to help you start by providing
# a starting point to customize your RDBMS installation for your site. 
# 
# NOTE: The values that are used in this file are only intended to be used
# as a starting point. You may want to adjust/tune those values to your
# specific hardware and needs. You may also consider using Database
# Configuration Assistant tool (DBCA) to create INIT file and to size your
# initial set of tablespaces based on the user input.
###############################################################################
 
# Change '<ORACLE_BASE>' to point to the oracle base (the one you specify at
# install time)
 
db_name='ORCL'
memory_target=1G
processes = 150
db_block_size=8192
db_domain=''
db_recovery_file_dest='<ORACLE_BASE>/flash_recovery_area'
db_recovery_file_dest_size=2G
diagnostic_dest='<ORACLE_BASE>'
dispatchers='(PROTOCOL=TCP) (SERVICE=ORCLXDB)'
open_cursors=300 
remote_login_passwordfile='EXCLUSIVE'
undo_tablespace='UNDOTBS1'
# You may want to ensure that control files are created on separate physical
# devices
control_files = (ora_control1, ora_control2)
compatible ='12.0.0'

2.6.1.2 Text Initialization Parameter File Format

The text initialization parameter file specifies the values of parameters in name/value pairs.

The text initialization parameter file (PFILE) must contain name/value pairs in one of the following forms:

  • For parameters that accept only a single value:

    parameter_name=value
    
  • For parameters that accept one or more values (such as the CONTROL_FILES parameter):

    parameter_name=(value[,value] ...)
    

Parameter values of type string must be enclosed in single quotes ('). Case (upper or lower) in file names is significant only if case is significant on the host operating system.

For parameters that accept multiple values, to enable you to easily copy and paste name/value pairs from the alert log, you can repeat a parameter on multiple lines, where each line contains a different value.

control_files='/u01/app/oracle/oradata/orcl/control01.ctl'
control_files='/u01/app/oracle/oradata/orcl/control02.ctl'
control_files='/u01/app/oracle/oradata/orcl/control03.ctl'

If you repeat a parameter that does not accept multiple values, then only the last value specified takes effect.

See Also:

2.6.2 Determining the Global Database Name

The global database name consists of the user-specified local database name and the location of the database within a network structure.

  • Set the DB_NAME and DB_DOMAIN initialization parameters.

The DB_NAME initialization parameter determines the local name component of the database name, and the DB_DOMAIN parameter, which is optional, indicates the domain (logical location) within a network structure. The combination of the settings for these two parameters must form a database name that is unique within a network.

For example, to create a database with a global database name of test.us.example.com, edit the parameters of the new parameter file as follows:

DB_NAME = test
DB_DOMAIN = us.example.com

You can rename the GLOBAL_NAME of your database using the ALTER DATABASE RENAME GLOBAL_NAME statement. However, you must also shut down and restart the database after first changing the DB_NAME and DB_DOMAIN initialization parameters and recreating the control files. Recreating the control files is easily accomplished with the command ALTER DATABASE BACKUP CONTROLFILE TO TRACE. See Oracle Database Backup and Recovery User's Guide for more information.

See Also:

Oracle Database Utilities for information about using the DBNEWID utility, which is another means of changing a database name

2.6.2.1 DB_NAME Initialization Parameter

The DB_NAME initialization parameter specifies a database identifier.

DB_NAME must be set to a text string of no more than 8 characters. The database name must start with an alphabetic character. During database creation, the name provided for DB_NAME is recorded in the data files, redo log files, and control file of the database. If during database instance startup the value of the DB_NAME parameter (in the parameter file) and the database name in the control file are different, then the database does not start.

2.6.2.2 DB_DOMAIN Initialization Parameter

In a distributed database system, the DB_DOMAIN initialization parameter specifies the logical location of the database within the network structure.

DB_DOMAIN is a text string that specifies the network domain where the database is created. If the database you are about to create will ever be part of a distributed database system, then give special attention to this initialization parameter before database creation. This parameter is optional.

See Also:

Distributed Database Management for more information about distributed databases

2.6.3 Specifying a Fast Recovery Area

The Fast Recovery Area is a location in which Oracle Database can store and manage files related to backup and recovery. It is distinct from the database area, which is a location for the current database files (data files, control files, and online redo logs).

Specify the Fast Recovery Area with the following initialization parameters:

  • DB_RECOVERY_FILE_DEST: Location of the Fast Recovery Area. This can be a directory, file system, or Automatic Storage Management (Oracle ASM) disk group.

    In an Oracle Real Application Clusters (Oracle RAC) environment, this location must be on a cluster file system, Oracle ASM disk group, or a shared directory configured through NFS.

  • DB_RECOVERY_FILE_DEST_SIZE: Specifies the maximum total bytes to be used by the Fast Recovery Area. This initialization parameter must be specified before DB_RECOVERY_FILE_DEST is enabled.

In an Oracle RAC environment, the settings for these two parameters must be the same on all instances.

You cannot enable these parameters if you have set values for the LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST parameters. You must disable those parameters before setting up the Fast Recovery Area. You can instead set values for the LOG_ARCHIVE_DEST_n parameters.

Oracle recommends using a Fast Recovery Area, because it can simplify backup and recovery operations for your database.

See Also:

Oracle Database Backup and Recovery User's Guide to learn how to create and use a Fast Recovery Area

2.6.4 Specifying Control Files

Every database has a control file, which contains entries that describe the structure of the database (such as its name, the timestamp of its creation, and the names and locations of its data files and redo files). The CONTROL_FILES initialization parameter specifies one or more names of control files, separated by commas.

  • Set the CONTROL_FILES initialization parameter.

When you execute the CREATE DATABASE statement, the control files listed in the CONTROL_FILES parameter are created.

If you do not include CONTROL_FILES in the initialization parameter file, then Oracle Database creates a control file in the same directory as the initialization parameter file, using a default operating system–dependent file name. If you have enabled Oracle Managed Files, the database creates Oracle managed control files.

If you want the database to create new operating system files when creating database control files, the file names listed in the CONTROL_FILES parameter must not match any file names that currently exist on your system. If you want the database to reuse or overwrite existing files when creating database control files, ensure that the file names listed in the CONTROL_FILES parameter match the file names that are to be reused, and include a CONTROLFILE REUSE clause in the CREATE DATABASE statement.

Oracle strongly recommends you use at least two control files stored on separate physical disk drives for each database.

2.6.5 Specifying Database Block Sizes

The DB_BLOCK_SIZE initialization parameter specifies the standard block size for the database.

  • Set the DB_BLOCK_SIZE initialization parameter.

This block size is used for the SYSTEM tablespace and by default in other tablespaces. Oracle Database can support up to four additional nonstandard block sizes.

2.6.5.1 DB_BLOCK_SIZE Initialization Parameter

The most commonly used block size should be picked as the standard block size. In many cases, this is the only block size that you must specify.

  • Set the DB_BLOCK_SIZE initialization parameter.

Typically, DB_BLOCK_SIZE is set to either 4K or 8K. If you do not set a value for this parameter, then the default data block size is operating system specific, which is generally adequate.

You cannot change the block size after database creation except by re-creating the database. If the database block size is different from the operating system block size, then ensure that the database block size is a multiple of the operating system block size. For example, if your operating system block size is 2K (2048 bytes), the following setting for the DB_BLOCK_SIZE initialization parameter is valid:

DB_BLOCK_SIZE=4096

A larger data block size provides greater efficiency in disk and memory I/O (access and storage of data). Therefore, consider specifying a block size larger than your operating system block size if the following conditions exist:

  • Oracle Database is on a large computer system with a large amount of memory and fast disk drives. For example, databases controlled by mainframe computers with vast hardware resources typically use a data block size of 4K or greater.

  • The operating system that runs Oracle Database uses a small operating system block size. For example, if the operating system block size is 1K and the default data block size matches this, the database may be performing an excessive amount of disk I/O during normal operation. For best performance in this case, a database block should consist of multiple operating system blocks.

    See Also:

    Your operating system specific Oracle documentation for details about the default block size.

2.6.5.2 Nonstandard Block Sizes

You can create tablespaces of nonstandard block sizes.

To create tablespaces of nonstandard block sizes:

  • Specify the BLOCKSIZE clause in a CREATE TABLESPACE statement.

These nonstandard block sizes can have any of the following power-of-two values: 2K, 4K, 8K, 16K or 32K. Platform-specific restrictions regarding the maximum block size apply, so some of these sizes may not be allowed on some platforms.

To use nonstandard block sizes, you must configure subcaches within the buffer cache area of the SGA memory for all of the nonstandard block sizes that you intend to use. The initialization parameters used for configuring these subcaches are described in "Using Automatic Shared Memory Management".

The ability to specify multiple block sizes for your database is especially useful if you are transporting tablespaces between databases. You can, for example, transport a tablespace that uses a 4K block size from an OLTP environment to a data warehouse environment that uses a standard block size of 8K.

Note:

A 32K block size is valid only on 64-bit platforms.

Caution:

Oracle recommends against specifying a 2K block size when 4K sector size disks are in use, because performance degradation can occur. For an explanation, see "Planning the Block Size of Redo Log Files".

2.6.6 Specifying the Maximum Number of Processes

The PROCESSES initialization parameter determines the maximum number of operating system processes that can be connected to Oracle Database concurrently.

  • Set the PROCESSES initialization parameter.

The value of this parameter must be a minimum of one for each background process plus one for each user process. The number of background processes will vary according the database features that you are using. For example, if you are using Advanced Queuing or the file mapping feature, then you will have additional background processes. If you are using Automatic Storage Management, then add three additional processes for the database instance.

If you plan on running 50 user processes, a good estimate would be to set the PROCESSES initialization parameter to 70.

2.6.7 Specifying the DDL Lock Timeout

You can specify the amount of time that blocking DDL statements wait for locks.

A data definition language (DDL) statement is either nonblocking or blocking, and both types of DDL statements require exclusive locks on internal structures. If these locks are unavailable when a DDL statement runs, then nonblocking and blocking DDL statements behave differently:

  • Nonblocking DDL waits until every concurrent DML transaction that references the object affected by the DDL either commits or rolls back.

  • Blocking DDL fails, though it might have succeeded if it had been executed subseconds later when the locks become available.

To enable blocking DDL statements to wait for locks, specify a DDL lock timeout—the number of seconds a DDL command waits for its required locks before failing.

  • To specify a DDL lock timeout, set the DDL_LOCK_TIMEOUT parameter.

The permissible range of values for DDL_LOCK_TIMEOUT is 0 to 1,000,000. The default is 0. You can set DDL_LOCK_TIMEOUT at the system level, or at the session level with an ALTER SESSION statement.

Note:

The DDL_LOCK_TIMEOUT parameter does not affect nonblocking DDL statements.

2.6.8 Specifying the Method of Undo Space Management

Every Oracle Database must have a method of maintaining information that is used to undo changes to the database. Such information consists of records of the actions of transactions, primarily before they are committed. Collectively these records are called undo data.

To set up an environment for automatic undo management using an undo tablespace.

  • Set the UNDO_MANAGEMENT initialization parameter to AUTO, which is the default.

See Also:

Managing Undo

2.6.8.1 UNDO_MANAGEMENT Initialization Parameter

The UNDO_MANAGEMENT initialization parameter determines whether an instance starts in automatic undo management mode, which stores undo in an undo tablespace. Set this parameter to AUTO to enable automatic undo management mode. AUTO is the default if the parameter is omitted or is null.

2.6.8.2 UNDO_TABLESPACE Initialization Parameter

The UNDO_TABLESPACE initialization parameter enables you to override that default undo tablespace for an instance.

When an instance starts up in automatic undo management mode, it attempts to select an undo tablespace for storage of undo data. If the database was created in automatic undo management mode, then the default undo tablespace (either the system-created SYS_UNDOTBS tablespace or the user-specified undo tablespace) is the undo tablespace used at instance startup. You can override this default for the instance by specifying a value for the UNDO_TABLESPACE initialization parameter. This parameter is especially useful for assigning a particular undo tablespace to an instance in an Oracle Real Application Clusters environment.

If no undo tablespace is specified by the UNDO_TABLESPACE initialization parameter, then the first available undo tablespace in the database is chosen. If no undo tablespace is available, then the instance starts without an undo tablespace, and undo data is written to the SYSTEM tablespace. You should avoid running in this mode.

Note:

When using the CREATE DATABASE statement to create a database, do not include an UNDO_TABLESPACE parameter in the initialization parameter file. Instead, include an UNDO TABLESPACE clause in the CREATE DATABASE statement.

2.6.9 Specifying the Database Compatibility Level

The COMPATIBLE initialization parameter controls the database compatibility level.

  • Set the COMPATIBLE initialization parameter to a release number.

2.6.9.1 About The COMPATIBLE Initialization Parameter

The COMPATIBLE initialization parameter enables or disables the use of features in the database that affect file format on disk. For example, if you create an Oracle Database 12c database, but specify COMPATIBLE=11.0.0 in the initialization parameter file, then features that require Oracle Database 12c compatibility generate an error if you try to use them. Such a database is said to be at the 11.0.0 compatibility level.

You can advance the compatibility level of your database by changing the COMPATIBLE initialization parameter. If you do, then there is no way to start the database using a lower compatibility level setting, except by doing a point-in-time recovery to a time before the compatibility was advanced.

The default value for the COMPATIBLE parameter is the release number of the most recent major release.

Note:

  • For Oracle Database 12c, the default value of the COMPATIBLE parameter is 12.0.0. The minimum value is 11.0.0. If you create an Oracle Database using the default value, then you can immediately use all the new features in this release, and you can never downgrade the database.

  • When you set this parameter in a server parameter file (SPFILE) using the ALTER SYSTEM statement, you must specify SCOPE=SPFILE, and you must restart the database for the change to take effect.

  • The COMPATIBLE initialization parameter must be specified as at least three decimal numbers with each pair separated by a dot, such as 12.0.0.

See Also:

2.6.10 Setting the License Parameter

If you use named user licensing, Oracle Database can help you enforce this form of licensing. You can set a limit on the number of users created in the database. Once this limit is reached, you cannot create more users.

Note:

This mechanism assumes that each person accessing the database has a unique user name and that no people share a user name. Therefore, so that named user licensing can help you ensure compliance with your Oracle license agreement, do not allow multiple users to log in using the same user name.

To limit the number of users created in a database, set the LICENSE_MAX_USERS initialization parameter in the database initialization parameter file.

The following example sets the LICENSE_MAX_USERS initialization parameter:

LICENSE_MAX_USERS = 200

Note:

Oracle no longer offers licensing by the number of concurrent sessions. Therefore the LICENSE_MAX_SESSIONS and LICENSE_SESSIONS_WARNING initialization parameters are no longer needed and have been deprecated.

2.7 Managing Initialization Parameters Using a Server Parameter File

Initialization parameters for the Oracle Database have traditionally been stored in a text initialization parameter file. For better manageability, you can choose to maintain initialization parameters in a binary server parameter file that is persistent across database startup and shutdown.

2.7.1 What Is a Server Parameter File?

A server parameter file can be thought of as a repository for initialization parameters that is maintained on the system running the Oracle Database server. It is, by design, a server-side initialization parameter file.

Initialization parameters stored in a server parameter file are persistent, in that any changes made to the parameters while an instance is running can persist across instance shutdown and startup. This arrangement eliminates the need to manually update initialization parameters to make persistent any changes effected by ALTER SYSTEM statements. It also provides a basis for self-tuning by the Oracle Database server.

A server parameter file is initially built from a text initialization parameter file using the CREATE SPFILE statement. (It can also be created directly by the Database Configuration Assistant.) The server parameter file is a binary file that cannot be edited using a text editor. Oracle Database provides other interfaces for viewing and modifying parameter settings in a server parameter file.

Note:

Although you can open the binary server parameter file with a text editor and view its text, do not manually edit it. Doing so will corrupt the file. You will not be able to start your instance, and if the instance is running, it could fail.

When you issue a STARTUP command with no PFILE clause, the Oracle instance searches an operating system–specific default location for a server parameter file from which to read initialization parameter settings. If no server parameter file is found, the instance searches for a text initialization parameter file. If a server parameter file exists but you want to override it with settings in a text initialization parameter file, you must specify the PFILE clause when issuing the STARTUP command. Instructions for starting an instance using a server parameter file are contained in "Starting Up a Database".

2.7.2 Migrating to a Server Parameter File

If you are currently using a text initialization parameter file, then you can migrate to a server parameter file.

To migrate to a server parameter file:

  1. If the initialization parameter file is located on a client system, then transfer the file (for example, FTP) from the client system to the server system.

    Note:

    If you are migrating to a server parameter file in an Oracle Real Application Clusters environment, you must combine all of your instance-specific initialization parameter files into a single initialization parameter file. Instructions for doing this and other actions unique to using a server parameter file for instances that are part of an Oracle Real Application Clusters installation are discussed in Oracle Real Application Clusters Administration and Deployment Guide and in your platform-specific Oracle Real Application Clusters Installation Guide.

  2. Create a server parameter file in the default location using the CREATE SPFILE FROM PFILE statement. See "Creating a Server Parameter File" for instructions.

    This statement reads the text initialization parameter file to create a server parameter file. The database does not have to be started to issue a CREATE SPFILE statement.

  3. Start up or restart the instance.

    The instance finds the new SPFILE in the default location and starts up with it.

2.7.3 Server Parameter File Default Names and Locations

Oracle recommends that you allow the database to give the SPFILE the default name and store it in the default location. This eases administration of your database. For example, the STARTUP command assumes this default location to read the SPFILE.

The following table shows the default name and location for both the text initialization parameter file (PFILE) and server parameter file (SPFILE) for the UNIX, Linux, and Windows platforms, both with and without the presence of Oracle Automatic Storage Management (Oracle ASM). The table assumes that the SPFILE is a file.

Table 2-3 PFILE and SPFILE Default Names and Locations on UNIX, Linux, and Windows

Platform PFILE Default Name SPFILE Default Name PFILE Default Location SPFILE Default Location

UNIX and Linux

initORACLE_SID.ora

spfileORACLE_SID.ora

Oracle_Home/dbs or the same location as the data files

Without Oracle ASM:

Oracle_Home/dbs or the same location as the data files

When Oracle ASM is present:

In the same disk group as the data files (assuming the database was created with DBCA)

Windows

initORACLE_SID.ora

spfileORACLE_SID.ora

Oracle_Home\database

Without Oracle ASM:

OH\database

When Oracle ASM is present:

In the same disk group as the data files (assuming the database was created with DBCA)

Note:

Upon startup, the instance first searches for an SPFILE named spfileORACLE_SID.ora, and if not found, searches for spfile.ora. Using spfile.ora enables all Real Application Cluster (Oracle RAC) instances to use the same server parameter file.

If neither SPFILE is found, the instance searches for the text initialization parameter file initORACLE_SID.ora.

If you create an SPFILE in a location other than the default location, you must create in the default PFILE location a "stub" PFILE that points to the server parameter file. For more information, see "Starting Up a Database".

When you create the database with DBCA when Oracle ASM is present, DBCA places the SPFILE in an Oracle ASM disk group, and also causes this stub PFILE to be created.

2.7.4 Creating a Server Parameter File

You use the CREATE SPFILE statement to create a server parameter file. You must have the SYSDBA, SYSOPER, or SYSBACKUP administrative privilege to execute this statement.

To create a server parameter file:

  • Run the CREATE SPFILE statement.

Note:

When you use the Database Configuration Assistant to create a database, it automatically creates a server parameter file for you.

The CREATE SPFILE statement can be executed before or after instance startup. However, if the instance has been started using a server parameter file, an error is raised if you attempt to re-create the same server parameter file that is currently being used by the instance.

You can create a server parameter file (SPFILE) from an existing text initialization parameter file or from memory. Creating the SPFILE from memory means copying the current values of initialization parameters in the running instance to the SPFILE.

The following example creates a server parameter file from text initialization parameter file /u01/oracle/dbs/init.ora. In this example no SPFILE name is specified, so the file is created with the platform-specific default name and location shown in Table 2-3.

CREATE SPFILE FROM PFILE='/u01/oracle/dbs/init.ora';

The next example illustrates creating a server parameter file and supplying a name and location.

CREATE SPFILE='/u01/oracle/dbs/test_spfile.ora'
       FROM PFILE='/u01/oracle/dbs/test_init.ora';

The next example illustrates creating a server parameter file in the default location from the current values of the initialization parameters in memory.

CREATE SPFILE FROM MEMORY;

Whether you use the default SPFILE name and default location or specify an SPFILE name and location, if an SPFILE of the same name already exists in the location, it is overwritten without a warning message.

When you create an SPFILE from a text initialization parameter file, comments specified on the same lines as a parameter setting in the initialization parameter file are maintained in the SPFILE. All other comments are ignored.

2.7.5 The SPFILE Initialization Parameter

The SPFILE initialization parameter contains the name of the current server parameter file.

When the default server parameter file is used by the database—that is, you issue a STARTUP command and do not specify a PFILE parameter—the value of SPFILE is internally set by the server. The SQL*Plus command SHOW PARAMETERS SPFILE (or any other method of querying the value of a parameter) displays the name of the server parameter file that is currently in use.

2.7.6 Changing Initialization Parameter Values

You can change initialization parameter values to affect the operation of a database instance.

2.7.6.1 About Changing Initialization Parameter Values

The ALTER SYSTEM statement enables you to set, change, or restore to default the values of initialization parameters. If you are using a text initialization parameter file, the ALTER SYSTEM statement changes the value of a parameter only for the current instance, because there is no mechanism for automatically updating text initialization parameters on disk. You must update them manually to be passed to a future instance. Using a server parameter file overcomes this limitation.

There are two kinds of initialization parameters:

  • Dynamic initialization parameters can be changed for the current Oracle Database instance. The changes take effect immediately.

  • Static initialization parameters cannot be changed for the current instance. You must change these parameters in the text initialization file or server parameter file and then restart the database before changes take effect.

2.7.6.2 Setting or Changing Initialization Parameter Values

With a server parameter file, use the SET clause of the ALTER SYSTEM statement to set or change initialization parameter values.

  • Run an ALTER SYSTEM SET statement.

For example, the following statement changes the maximum number of failed login attempts before the connection is dropped. It includes a comment, and explicitly states that the change is to be made only in the server parameter file.

ALTER SYSTEM SET SEC_MAX_FAILED_LOGIN_ATTEMPTS=3
                 COMMENT='Reduce from 10 for tighter security.'
                 SCOPE=SPFILE;

The next example sets a complex initialization parameter that takes a list of attributes. Specifically, the parameter value being set is the LOG_ARCHIVE_DEST_n initialization parameter. This statement could change an existing setting for this parameter or create a new archive destination.

ALTER SYSTEM 
     SET LOG_ARCHIVE_DEST_4='LOCATION=/u02/oracle/rbdb1/',MANDATORY,'REOPEN=2'
         COMMENT='Add new destination on Nov 29'
         SCOPE=SPFILE;

When a value consists of a list of parameters, you cannot edit individual attributes by the position or ordinal number. You must specify the complete list of values each time the parameter is updated, and the new list completely replaces the old list.

2.7.6.2.1 The SCOPE Clause in ALTER SYSTEM SET Statements

The optional SCOPE clause in ALTER SYSTEM SET statements specifies the scope of an initialization parameter change.

SCOPE Clause Description

SCOPE = SPFILE

The change is applied in the server parameter file only. The effect is as follows:

  • No change is made to the current instance.

  • For both dynamic and static parameters, the change is effective at the next startup and is persistent.

This is the only SCOPE specification allowed for static parameters.

SCOPE = MEMORY

The change is applied in memory only. The effect is as follows:

  • The change is made to the current instance and is effective immediately.

  • For dynamic parameters, the effect is immediate, but it is not persistent because the server parameter file is not updated.

For static parameters, this specification is not allowed.

SCOPE = BOTH

The change is applied in both the server parameter file and memory. The effect is as follows:

  • The change is made to the current instance and is effective immediately.

  • For dynamic parameters, the effect is persistent because the server parameter file is updated.

For static parameters, this specification is not allowed.

It is an error to specify SCOPE=SPFILE or SCOPE=BOTH if the instance did not start up with a server parameter file. The default is SCOPE=BOTH if a server parameter file was used to start up the instance, and MEMORY if a text initialization parameter file was used to start up the instance.

For dynamic parameters, you can also specify the DEFERRED keyword. When specified, the change is effective only for future sessions.

When you specify SCOPE as SPFILE or BOTH, an optional COMMENT clause lets you associate a text string with the parameter update. The comment is written to the server parameter file.

2.7.7 Clearing Initialization Parameter Values

You can use the ALTER SYSTEM RESET statement to clear (remove) the setting of any initialization parameter in the SPFILE that was used to start the instance. You may want to clear a parameter in the SPFILE so that upon the next database startup a default value is used.

  • Run an ALTER SYSTEM RESET statement.

Neither SCOPE=MEMORY nor SCOPE=BOTH are allowed. The SCOPE = SPFILE clause is not required, but can be included.

See Also:

Oracle Database SQL Language Reference for information about the ALTER SYSTEM command

2.7.8 Exporting the Server Parameter File

You can use the CREATE PFILE statement to export a server parameter file (SPFILE) to a text initialization parameter file.

  • Run a CREATE PFILE statement.

Exporting the server parameter file might be necessary for several reasons:

  • For diagnostic purposes, listing all of the parameter values currently used by an instance. This is analogous to the SQL*Plus SHOW PARAMETERS command or selecting from the V$PARAMETER or V$PARAMETER2 views.

  • To modify the server parameter file by first exporting it, editing the resulting text file, and then re-creating it using the CREATE SPFILE statement

The exported file can also be used to start up an instance using the PFILE clause.

You must have the SYSDBA, SYSOPER, or SYSBACKUP administrative privilege to execute the CREATE PFILE statement. The exported file is created on the database server system. It contains any comments associated with the parameter in the same line as the parameter setting.

The following example creates a text initialization parameter file from the SPFILE:

CREATE PFILE FROM SPFILE;

Because no names were specified for the files, the database creates an initialization parameter file with a platform-specific name, and it is created from the platform-specific default server parameter file.

The following example creates a text initialization parameter file from a server parameter file, but in this example the names of the files are specified:

CREATE PFILE='/u01/oracle/dbs/test_init.ora'
  FROM SPFILE='/u01/oracle/dbs/test_spfile.ora';

Note:

An alternative is to create a PFILE from the current values of the initialization parameters in memory. The following is an example of the required command:

CREATE PFILE='/u01/oracle/dbs/test_init.ora' FROM MEMORY;

2.7.9 Backing Up the Server Parameter File

You can create a backup of your server parameter file (SPFILE) by exporting it. If the backup and recovery strategy for your database is implemented using Recovery Manager (RMAN), then you can use RMAN to create a backup of the SPFILE. The SPFILE is backed up automatically by RMAN when you back up your database, but RMAN also enables you to specifically create a backup of the currently active SPFILE.

  • Back up the server parameter file either by exporting it or by using RMAN.

2.7.10 Recovering a Lost or Damaged Server Parameter File

You can recover the server parameter file (SPFILE). If your server parameter file (SPFILE) becomes lost or corrupted, then the current instance may fail, or the next attempt at starting the database instance may fail.

There are several ways to recover the SPFILE:

  • If the instance is running, issue the following command to re-create the SPFILE from the current values of initialization parameters in memory:

    CREATE SPFILE FROM MEMORY;
    

    This command creates the SPFILE with the default name and in the default location. You can also create the SPFILE with a new name or in a specified location. See "Creating a Server Parameter File" for examples.

  • If you have a valid text initialization parameter file (PFILE), re-create the SPFILE from the PFILE with the following statement:

    CREATE SPFILE FROM PFILE;
    

    This command assumes that the PFILE is in the default location and has the default name. See "Creating a Server Parameter File" for the command syntax to use when the PFILE is not in the default location or has a nondefault name.

  • Restore the SPFILE from backup.

    See "Backing Up the Server Parameter File" for more information.

  • If none of the previous methods are possible in your situation, perform these steps:

    1. Create a text initialization parameter file (PFILE) from the parameter value listings in the alert log.

      When an instance starts up, the initialization parameters used for startup are written to the alert log. You can copy and paste this section from the text version of the alert log (without XML tags) into a new PFILE.

      See "Viewing the Alert Log" for more information.

    2. Create the SPFILE from the PFILE.

      See "Creating a Server Parameter File" for instructions.

Read/Write Errors During a Parameter Update

If an error occurs while reading or writing the server parameter file during a parameter update, the error is reported in the alert log and all subsequent parameter updates to the server parameter file are ignored. At this point, you can take one of the following actions:

  • Shut down the instance, recover the server parameter file and described earlier in this section, and then restart the instance.

  • Continue to run the database if you do not care that subsequent parameter updates will not be persistent.

2.7.11 Methods for Viewing Parameter Settings

You can view parameter settings using several different methods.

Method Description

SHOW PARAMETERS

This SQL*Plus command displays the values of initialization parameters in effect for the current session.

SHOW SPPARAMETERS

This SQL*Plus command displays the values of initialization parameters in the server parameter file (SPFILE).

CREATE PFILE

This SQL statement creates a text initialization parameter file (PFILE) from the SPFILE or from the current in-memory settings. You can then view the PFILE with any text editor.

V$PARAMETER

This view displays the values of initialization parameters in effect for the current session.

V$PARAMETER2

This view displays the values of initialization parameters in effect for the current session. It is easier to distinguish list parameter values in this view because each list parameter value appears in a separate row.

V$SYSTEM_PARAMETER

This view displays the values of initialization parameters in effect for the instance. A new session inherits parameter values from the instance-wide values.

V$SYSTEM_PARAMETER2

This view displays the values of initialization parameters in effect for the instance. A new session inherits parameter values from the instance-wide values. It is easier to distinguish list parameter values in this view because each list parameter value appears in a separate row.

V$SPPARAMETER

This view displays the current contents of the SPFILE. The view returns FALSE values in the ISSPECIFIED column if an SPFILE is not being used by the instance.

See Also:

Oracle Database Reference for a complete description of views

2.8 Managing Application Workloads with Database Services

A database service is a named representation of one or more database instances. Services enable you to group database workloads and route a particular work request to an appropriate instance.

2.8.1 Database Services

A database service represents a single database. This database can be a single-instance database or an Oracle Real Application Clusters (Oracle RAC) database with multiple concurrent database instances. A global database service is a service provided by multiple databases synchronized through data replication.

2.8.1.1 About Database Services

Database services divide workloads for a single database into mutually disjoint groupings.

Each database service represents a workload with common attributes, service-level thresholds, and priorities. The grouping is based on attributes of work that might include the application function to be used, the priority of execution for the application function, the job class to be managed, or the data range used in the application function or job class. For example, the Oracle E-Business Suite defines a database service for each responsibility, such as general ledger, accounts receivable, order entry, and so on. When you configure database services, you give each service a unique name, associated performance goals, and associated importance. The database services are tightly integrated with Oracle Database and are maintained in the data dictionary.

Connection requests can include a database service name. Thus, middle-tier applications and client/server applications use a service by specifying the database service as part of the connection in TNS connect data. If no database service name is included and the Net Services file listener.ora designates a default database service, then the connection uses the default database service.

Database services enable you to configure a workload for a single database, administer it, enable and disable it, and measure the workload as a single entity. You can do this using standard tools such as the Database Configuration Assistant (DBCA), Oracle Net Configuration Assistant, and Oracle Enterprise Manager Cloud Control (Cloud Control). Cloud Control supports viewing and operating services as a whole, with drill down to the instance-level when needed.

In an Oracle Real Application Clusters (Oracle RAC) environment, a database service can span one or more instances and facilitate workload balancing based on transaction performance. This capability provides end-to-end unattended recovery, rolling changes by workload, and full location transparency. Oracle RAC also enables you to manage several database service features with Cloud Control, the DBCA, and the Server Control utility (SRVCTL).

Database services describe applications, application functions, and data ranges as either functional services or data-dependent services. Functional services are the most common mapping of workloads. Sessions using a particular function are grouped together. In contrast, data-dependent routing routes sessions to database services based on data keys. The mapping of work requests to database services occurs in the object relational mapping layer for application servers and TP monitors. For example, in Oracle RAC, these ranges can be completely dynamic and based on demand because the database is shared.

In addition to database services that are used by applications, Oracle Database also supports two internal database services: SYS$BACKGROUND is used by the background processes only, and SYS$USERS is the default database service for user sessions that are not associated with services.

Using database services requires no changes to your application code. Client-side work can connect to a named database service. Server-side work, such as Oracle Scheduler, parallel execution, and Oracle Database Advanced Queuing, set the database service name as part of the workload definition. Work requests executing under a database service inherit the performance thresholds for the service and are measured as part of the service.

See Also:

2.8.1.2 Database Services and Performance

Database services offer an extra dimension in performance tuning.

Tuning by "service and SQL" can replace tuning by "session and SQL" in the majority of systems where all sessions are anonymous and shared. With database services, workloads are visible and measurable. Resource consumption and waits are attributable by application. Additionally, resources assigned to database services can be augmented when loads increase or decrease. This dynamic resource allocation enables a cost-effective solution for meeting demands as they occur. For example, database services are measured automatically, and the performance is compared to service-level thresholds. Performance violations are reported to Cloud Control, enabling the execution of automatic or scheduled solutions.

2.8.1.3 Oracle Database Features That Use Database Services

Several Oracle Database features support database services.

The Automatic Workload Repository (AWR) manages the performance of services. AWR records database service performance, including execution times, wait classes, and resources consumed by services. AWR alerts warn when database service response time thresholds are exceeded. The dynamic views report current service performance metrics with one hour of history. Each database service has quality-of-service thresholds for response time and CPU consumption.

In addition, the Database Resource Manager can map database services to consumer groups. Therefore, you can automatically manage the priority of one database service relative to others. You can use consumer groups to define relative priority in terms of either ratios or resource consumption. This is described in more detail in Managing Resources with Oracle Database Resource Manager, and specifically in "Specifying Session-to–Consumer Group Mapping Rules".

You also can specify an edition attribute for a database service. Editions make it possible to have two or more versions of the same objects in the database. When you specify an edition attribute for a database service, all subsequent connections that specify the database service use this edition as the initial session edition. This is described in more detail in "Setting the Edition Attribute of a Database Service".

Specifying an edition as a database service attribute can make it easier to manage resource usage. For example, database services associated with an edition can be placed on a separate instance in an Oracle RAC environment, and the Database Resource Manager can manage resources used by different editions by associating resource plans with the corresponding database services.

For Oracle Scheduler, you optionally assign a database service when you create a job class. During execution, jobs are assigned to job classes, and job classes can run within database services. Using database services with job classes ensures that the work executed by the job scheduler is identified for workload management and performance tuning.

For parallel query and parallel DML, the query coordinator connects to a database service just like any other client. The parallel query processes inherit the database service for the duration of the execution. At the end of query execution, the parallel execution processes revert to the default database service.

See Also:

Scheduling Jobs with Oracle Scheduler for more information about the Oracle Scheduler

2.8.1.4 Creating Database Services

There are a few ways to create database services, depending on your database configuration.

Note:

This section describes creating services locally. You can also create services to operate globally. See "Global Data Services" for more information.

To create a database service:

  • If your single-instance database is being managed by Oracle Restart, use the SRVCTL utility to create the database service.

    srvctl add service -db db_unique_name -service service_name
    
  • If your single-instance database is not being managed by Oracle Restart, do one of the following:

    • Append the desired database service name to the SERVICE_NAMES parameter.

    • Call the DBMS_SERVICE.CREATE_SERVICE package procedure.

  • (Optional) Define database service attributes with Cloud Control or with DBMS_SERVICE.MODIFY_SERVICE.

Oracle Net Listener (the listener) receives incoming client connection requests and manages the traffic of these requests to the database server. The listener handles connections for registered services, and it supports dynamic service registration.

See Also:

2.8.2 Global Data Services

Starting with Oracle Database 12c, you can use Global Data Services (GDS) for workload management involving multiple Oracle databases. GDS enables administrators to automatically and transparently manage client workloads across replicated databases that offer common services. These common services are known as global services.

GDS enables you to integrate multiple databases in various locations into private GDS configurations that can be shared by global clients. Benefits include the following:

  • Enables central management of global resources

  • Provides global scalability, availability, and run-time load balancing

  • Allows you to dynamically add databases to the GDS configuration and dynamically migrate global services

  • Extends service management, load balancing, and failover capabilities for distributed environments of replicated databases that use features such as Oracle Active Data Guard, Oracle GoldenGate, and so on

  • Provides high availability through seamless failover of global services across databases (located both locally or globally)

  • Provides workload balancing both within and between data centers through services, connection load balancing, and runtime load balancing

  • Allows efficient utilization of the resources of the GDS configuration to service client requests

2.8.3 Database Service Data Dictionary Views

You can query data dictionary views to find information about database services.

You can find information about database services in the following views:

The following additional views also contain some information about database services:

The ALL_SERVICES view includes a GLOBAL_SERVICE column, and the V$SERVICES and V$ACTIVE_SERVICES views contain a GLOBAL column. These views and columns enable you to determine whether a database service is a global service.

2.9 Considerations After Creating a Database

After you create a database the instance is left running, and the database is open and available for normal database use. You may want to perform specific actions after creating a database.

2.9.1 Some Security Considerations

Configure your database so that it is secure.

You can find security guidelines for this release in Oracle Database Security Guide. Oracle recommends that you read these guidelines and configure your database accordingly.

After the database is created, you can configure it to take advantage of Oracle Identity Management.

A newly created database has at least three user accounts that are important for administering your database: SYS, SYSTEM, and SYSMAN. Additional administrative accounts are provided that should be used only by authorized users. To protect these accounts from being used by unauthorized users familiar with their Oracle-supplied passwords, these accounts are initially locked with their passwords expired. As the database administrator, you are responsible for the unlocking and resetting of these accounts.

Note:

To prevent unauthorized access and protect the integrity of your database, it is important that new passwords for user accounts SYS and SYSTEM be specified when the database is created. This is accomplished by specifying the following CREATE DATABASE clauses when manually creating you database, or by using DBCA to create the database:

  • USER SYS IDENTIFIED BY

  • USER SYSTEM IDENTIFIED BY

See Also:

2.9.2 Transparent Data Encryption

Transparent Data Encryption is a feature that enables encryption of individual database columns before storing them in the data file, or enables encryption of entire tablespaces. If users attempt to circumvent the database access control mechanisms by looking inside data files directly with operating system tools, Transparent Data Encryption prevents such users from viewing sensitive information.

Users who have the CREATE TABLE privilege can choose one or more columns in a table to be encrypted. The data is encrypted in the data files. Database users with appropriate privileges can view the data in unencrypted format. For information on enabling Transparent Data Encryption, see Oracle Database Advanced Security Guide.

2.9.3 A Secure External Password Store

For large-scale deployments where applications use password credentials to connect to databases, it is possible to store such credentials in a client-side Oracle wallet. An Oracle wallet is a secure software container that is used to store authentication and signing credentials.

Storing database password credentials in a client-side Oracle wallet eliminates the need to embed usernames and passwords in application code, batch jobs, or scripts. This reduces the risk of exposing passwords in the clear in scripts and application code, and simplifies maintenance because you need not change your code each time usernames and passwords change. In addition, not having to change application code also makes it easier to enforce password management policies for these user accounts.

When you configure a client to use the external password store, applications can use the following syntax to connect to databases that use password authentication:

CONNECT /@database_alias

Note that you need not specify database login credentials in this CONNECT command. Instead your system looks for database login credentials in the client wallet.

2.9.4 Transaction Guard and Application Continuity

Transaction Guard uses a logical transaction ID to prevent the possibility of a client application submitting duplicate transactions after a recoverable error. Application Continuity enables the replay, in a nondisruptive and rapid manner, of a request against the database after a recoverable error that makes the database session unavailable.

Transaction Guard is a reliable protocol and API that application developers can use to provide a known outcome for the last open transaction on a database session that becomes unavailable. After an outage, the commit message that is sent from the database to the client is not durable. If the connection breaks between an application (the client) and an Oracle database (the server), then the client receives an error message indicating that the communication failed. This error message does not inform the client about the success or failure of commit operations or procedure calls.

Transaction Guard uses a new concept called the logical transaction identifier (LTXID), a globally unique identifier that identifies the transaction from the application's perspective. When a recoverable outage occurs, the application uses the LTXID to determine the outcome of the transaction. This outcome can be returned to the client instead of the ambiguous communication error. The user can decide whether to resubmit the transaction. The application also can be coded to resubmit the transaction if the states are correct.

Application Continuity masks outages from end users and applications by recovering the in-flight database sessions following recoverable outages, for both unplanned and planned outages. After a successful replay, the application can continue where that database session left off. Application Continuity performs this recovery so that the outage appears to the application as a delayed execution.

Application Continuity is enabled at the service level and is invoked for outages that are recoverable. These outages typically are related to underlying software, foreground, hardware, communications, network, or storage layers. Application Continuity supports queries, alter sessions, PL/SQL, and the last uncommitted transaction before the failure. Application Continuity determines whether the last in-flight operation committed or not, and completed or not, using Transaction Guard.

See Also:

2.9.5 The Oracle Database Sample Schemas

Oracle Database includes sample schemas that help you to become familiar with Oracle Database functionality. All Oracle Database documentation and training materials are being converted to the Sample Schemas environment as those materials are updated.

The Oracle Database distribution media includes various SQL files that let you experiment with the system, learn SQL, or create additional tables, views, or synonyms.

The Sample Schemas can be installed automatically by the Database Configuration Assistant, or you can install them manually. The schemas and installation instructions are described in detail in Oracle Database Sample Schemas.

2.10 Cloning a Database with CloneDB

CloneDB enables you to clone a database multiple times without copying the data files into several different locations. Instead, CloneDB uses copy-on-write technology, so that only the blocks that are modified require additional storage on disk.

2.10.1 About Cloning a Database with CloneDB

It is often necessary to clone a production database for testing purposes or other purposes.

Common reasons to clone a production database include the following:

  • Deployment of a new application, or an update of an existing application, that uses the database

  • A planned operating system upgrade on the system that runs the database

  • New storage for the database installation

  • Reporting

  • Analysis of older data

Before deploying a new application, performing an operating system upgrade, or using new storage, thorough testing is required to ensure that the database works properly under the new conditions. Cloning can be achieved by making copies of the production data files in one or more test environments, but these copies typically require large amounts of storage space to be allocated and managed.

With CloneDB, you can clone a database multiple times without copying the data files into several different locations. Instead, Oracle Database creates the files in the CloneDB database using copy-on-write technology, so that only the blocks that are modified in the CloneDB database require additional storage on disk.

Cloning a database in this way provides the following advantages:

  • It reduces the amount of storage required for testing purposes.

  • It enables the rapid creation of multiple database clones for various purposes.

The CloneDB databases use the data files of a database backup. Using the backup data files ensures that the production data files are not accessed by the CloneDB instances and that the CloneDB instances do not compete for the production database's resources, such as CPU and I/O resources.

The instructions in this chapter describe cloning a non-CDB. You can also clone a pluggable database (PDB) in a CDB using the CREATE PLUGGABLE DATABASE statement. If your underlying file system supports storage snapshots, then you can use the SNAPSHOT COPY clause of the CREATE PLUGGABLE DATABASE statement to clone a PDB using a storage snapshot.

Note:

The CloneDB feature is not intended for performance testing.

2.10.2 Cloning a Database with CloneDB

You can clone a database with CloneDB.

Before cloning a database, the following prerequisites must be met:

  • Each CloneDB database must use Direct NFS Client, and the backup of the production database must be located on an NFS volume.

    Direct NFS Client enables an Oracle database to access network attached storage (NAS) devices directly, rather than using the operating system kernel NFS client. This CloneDB database feature is available on platforms that support Direct NFS Client.

    See Oracle Grid Infrastructure Installation Guide for your operating system for information about Direct NFS Client.

  • At least 2 MB of additional System Global Area (SGA) memory is required to track the modified blocks in a CloneDB database.

    See Managing Memory.

  • Storage for the database backup and for the changed blocks in each CloneDB database is required.

    The storage required for the database backup depends on the method used to perform the backup. A single full RMAN backup requires the most storage. Storage snapshots carried out using the features of a storage appliance adhere to the requirements of the storage appliance. A single backup can support multiple CloneDB databases.

    The amount of storage required for each CloneDB database depends on the write activity in that database. Every block that is modified requires an available block of storage. Therefore, the total storage requirement depends on the number of blocks modified in the CloneDB database over time.

This section describes the steps required to create one CloneDB database and uses these sample databases and directories:

  • The Oracle home for the production database PROD1 is /u01/prod1/oracle.

  • The files for the database backup are in /u02/oracle/backup/prod1.

  • The Oracle home for CloneDB database CLONE1 is /u03/clone1/oracle.

To clone a database with CloneDB:

  1. Create a backup of your production database. You have the following backup options:

    • An online backup

      If you perform an online backup, then ensure that your production database is in ARCHIVELOG mode and that all of the necessary archived redo log files are saved and accessible to the CloneDB database environment.

    • A full offline backup

      If you perform a full offline backup, then ensure that the backup files are accessible to the CloneDB database environment.

    • A backup that copies the database files

      If you specify BACKUP AS COPY in RMAN, then RMAN copies each file as an image copy, which is a bit-for-bit copy of a database file created on disk. Image copies are identical to copies created with operating system commands such as cp on Linux or COPY on Windows, but are recorded in the RMAN repository and so are usable by RMAN. You can use RMAN to make image copies while the database is open. Ensure that the copied database files are accessible to the CloneDB database environment.

    See Oracle Database Backup and Recovery User's Guide for information about backing up a database.

  2. Create a text initialization parameter file (PFILE) if one does not exist.

    If you are using a server parameter file (SPFILE), then run the following statement on the production database to create a PFILE:

    CREATE PFILE FROM SPFILE;
    
  3. Create SQL scripts for cloning the production database.

    You will use one or more SQL scripts to create a CloneDB database in a later step. To create the SQL scripts, you can either use an Oracle-supplied Perl script called clonedb.pl, or you can create a SQL script manually.

    To use the clonedb.pl Perl script, complete the following steps:

    1. Set the following environment variables at an operating system prompt:

      MASTER_COPY_DIR - Specify the directory that contains the backup created in Step 1. Ensure that this directory contains only the backup of the data files of the production database.

      CLONE_FILE_CREATE_DEST - Specify the directory where CloneDB database files will be created, including data files, log files, control files.

      CLONEDB_NAME - Specify the name of the CloneDB database.

      S7000_TARGET - If the NFS host providing the file system for the backup and the CloneDB database is a Sun Storage 7000, then specify the name of the host. Otherwise, do not set this environment variable. Set this environment variable only if cloning must be done using storage snapshots. You can use S7000 storage arrays for Direct NFS Client without setting this variable.

    2. Run the clonedb.pl Perl script.

      The script is in the $ORACLE_HOME/rdbms/install directory and has the following syntax:

      $ORACLE_HOME/perl/bin/perl $ORACLE_HOME/rdbms/install/clonedb.pl 
      prod_db_pfile [sql_script1] [sql_script2]
      

      Specify the following options:

      prod_db_pfile - Specify the full path of the production database's PFILE.

      sql_script1 - Specify a name for the first SQL script generated by clonedb.pl. The default is crtdb.sql.

      sql_script2 - Specify a name for the second SQL script generated by clonedb.pl. The default is dbren.sql.

      The clonedb.pl script copies the production database's PFILE to the CloneDB database's directory. It also creates two SQL scripts that you will use to create the CloneDB database.

    3. Check the two SQL scripts that were generated by the clonedb.pl Perl script, and make changes if necessary.

    4. Modify the initialization parameters for the CloneDB database environment, and save the file.

      Change any initialization parameter that is specific to the CloneDB database environment, such as parameters that control SGA size, PGA target, the number of CPUs, and so on. The CLONEDB parameter must be set to TRUE, and the initialization parameter file includes this parameter. See Oracle Database Reference for information about initialization parameters.

    5. In SQL*Plus, connect to the CloneDB database with SYSDBA administrative privilege.

    6. Run the SQL scripts generated by the clonedb.pl Perl script.

      For example, if the scripts use the default names, then run the following scripts at the SQL prompt:

      crtdb.sql
      dbren.sql
      

    To create a SQL script manually, complete the following steps:

    1. Connect to the database with SYSDBA or SYSBACKUP administrative privilege.

      See "Connecting to the Database with SQL*Plus".

    2. Generate a backup control file script from your production database by completing the following steps:

      Run the following SQL statement:

      ALTER DATABASE BACKUP CONTROLFILE TO TRACE;
      

      This statement generates a trace file that contains the SQL statements that create the control file. The trace file containing the CREATE CONTROLFILE statement is stored in a directory determined by the DIAGNOSTIC_DEST initialization parameter. Check the database alert log for the name and location of this trace file.

    3. Open the trace file generated in Step 3.b, and copy the STARTUP NOMOUNT and CREATE CONTROLFILE statements in the trace file to a new SQL script.

    4. Edit the new SQL script you created in Step 3.c in the following ways:

      Change the name of the database to the name of the CloneDB database you are creating. For example, change PROD1 to CLONE1.

      Change the locations of the log files to a directory in the CloneDB database environment. For example, change/u01/prod1/oracle/dbs/t_log1.f to /u03/clone1/oracle/dbs/t_log1.f.

      Change the locations of the data files to the backup location. For example, change /u01/prod1/oracle/dbs/t_db1.f to /u02/oracle/backup/prod1/t_db1.f.

      The following is an example of the original statements generated by the ALTER DATABASE BACKUP CONTROLFILE TO TRACE statement:

      STARTUP NOMOUNT
      CREATE CONTROLFILE REUSE DATABASE "PROD1" NORESETLOGS  ARCHIVELOG
          MAXLOGFILES 32
          MAXLOGMEMBERS 2
          MAXDATAFILES 32
          MAXINSTANCES 1
          MAXLOGHISTORY 292
      LOGFILE
        GROUP 1 '/u01/prod1/oracle/dbs/t_log1.f'  SIZE 25M BLOCKSIZE 512,
        GROUP 2 '/u01/prod1/oracle/dbs/t_log2.f'  SIZE 25M BLOCKSIZE 512
      -- STANDBY LOGFILE
      DATAFILE
        '/u01/prod1/oracle/dbs/t_db1.f',
        '/u01/prod1/oracle/dbs/t_ax1.f',
        '/u01/prod1/oracle/dbs/t_undo1.f',
        '/u01/prod1/oracle/dbs/t_xdb1.f',
        '/u01/prod1/oracle/dbs/undots.dbf'
      CHARACTER SET WE8ISO8859P1
      ;
      

      The following is an example of the modified statements in the new SQL script:

      STARTUP NOMOUNT PFILE=/u03/clone1/oracle/dbs/clone1.ora
      CREATE CONTROLFILE REUSE DATABASE "CLONE1" RESETLOGS  ARCHIVELOG
          MAXLOGFILES 32
          MAXLOGMEMBERS 2
          MAXDATAFILES 32
          MAXINSTANCES 1
          MAXLOGHISTORY 292
      LOGFILE
        GROUP 1 '/u03/clone1/oracle/dbs/t_log1.f'  SIZE 25M BLOCKSIZE 512,
        GROUP 2 '/u03/clone1/oracle/dbs/t_log2.f'  SIZE 25M BLOCKSIZE 512
      -- STANDBY LOGFILE
      DATAFILE
        '/u02/oracle/backup/prod1/t_db1.f',
        '/u02/oracle/backup/prod1/t_ax1.f',
        '/u02/oracle/backup/prod1/t_undo1.f',
        '/u02/oracle/backup/prod1/t_xdb1.f',
        '/u02/oracle/backup/prod1/undots.dbf'
      CHARACTER SET WE8ISO8859P1
      ;
      

      If you have a storage level snapshot taken on a data file, then you can replace the RMAN backup file names with the storage snapshot names.

    5. After you edit the SQL script, save it to a location that is accessible to the CloneDB database environment.

      Make a note of the name and location of the new SQL script. You will run the script in a subsequent step. In this example, assume the name of the script is create_clonedb1.sql

    6. Copy the text initialization parameter file (PFILE) from the production database environment to the CloneDB database environment.

      For example, copy the text initialization parameter file from /u01/prod1/oracle/dbs to /u03/clone1/oracle/dbs. The name and location of the file must match the name and location specified in the STARTUP NOMOUNT command in the modified SQL script. In the example in Step 3.d, the file is /u03/clone1/oracle/dbs/clone1.ora.

    7. Modify the initialization parameters for the CloneDB database environment, and save the file.

      Add the CLONEDB parameter, and ensure that this parameter is set to TRUE. Change any other initialization parameter that is specific to the CloneDB database environment, such as parameters that control SGA size, PGA target, the number of CPUs, and so on. See Oracle Database Reference for information about initialization parameters.

    8. In SQL*Plus, connect to the CloneDB database with SYSDBA administrative privilege.

    9. Run the SQL script you saved in Step 3.e.

      For example, enter the following in SQL*Plus:

      @create_clonedb1.sql
      
    10. For each data file in the backup location, run the CLONEDB_RENAMEFILE procedure in the DBMS_DNFS package and specify the appropriate location in the CloneDB database environment.

      For example, run the following procedure if the backup data file is /u02/oracle/backup/prod1/t_db1.f and the CloneDB database data file is /u03/clone1/oracle/dbs/t_db1.f:

      BEGIN
        DBMS_DNFS.CLONEDB_RENAMEFILE(
          srcfile  => '/u02/oracle/backup/prod1/t_db1.f',
          destfile => '/u03/clone1/oracle/dbs/t_db1.f');
      END;
      /
      

      See Oracle Database PL/SQL Packages and Types Reference for more information about the DBMS_DNFS package.

  4. If you created your CloneDB database from an online backup, then recover the CloneDB database. This step is not required if you performed a full offline backup or a BACKUP AS COPY backup.

    For example, run the following SQL statement on the CloneDB database:

    RECOVER DATABASE USING BACKUP CONTROLFILE UNTIL CANCEL;
    

    This statement prompts for the archived redo log files for the period when the backup was performed.

  5. Open the database by running the following SQL statement:

    ALTER DATABASE OPEN RESETLOGS;
    

    The CloneDB database is ready for use.

To create additional CloneDB databases of the production database, repeat Steps 3 - 5 for each CloneDB database.

2.10.3 After Cloning a Database with CloneDB

After a CloneDB database is created, you can use it in almost any way you use your production database. Initially, a CloneDB database uses a minimal amount of storage for each data file. Changes to rows in a CloneDB database cause storage space to be allocated on demand.

You can use the same backup files to create multiple CloneDB databases. This backup can be taken either by RMAN or by storage level snapshots. If you have a storage level snapshot taken on a data file, then you can replace the RMAN backup file names with the storage snapshot names.

You can use the V$CLONEDFILE view to show information about each data file in the CloneDB database. This information includes the data file name in the backup, the corresponding data file name in the CloneDB database, the number of blocks read from the backup file, and the number of requests issued against the backup file.

Because CloneDB databases use the backup files as their backend storage, the backup files must be available to each CloneDB database for it to run. If the backup files become unavailable, then the CloneDB databases return errors.

When your use of a CloneDB database is complete, you can destroy the CloneDB database environment. You can delete all of the files in the CloneDB database environment without affecting the production database environment or the backup environment.

See Also:

Oracle Database Reference for more information about the V$CLONEDFILE view

2.11 Dropping a Database

Dropping a database involves removing its data files, online redo logs, control files, and initialization parameter files.

WARNING:

Dropping a database deletes all data in the database.

To drop a database:

  • Submit the following statement:

    DROP DATABASE;
    

The DROP DATABASE statement first deletes all control files and all other database files listed in the control file. It then shuts down the database instance.

To use the DROP DATABASE statement successfully, the database must be mounted in exclusive and restricted mode.

The DROP DATABASE statement has no effect on archived redo log files, nor does it have any effect on copies or backups of the database. It is best to use RMAN to delete such files.

If you used the Database Configuration Assistant to create your database, you can use that tool to delete (drop) your database and remove the files.

2.12 Database Data Dictionary Views

You can query data dictionary views for information about your database content and structure.

You can view information about your database content and structure using the following views:

View Description

DATABASE_PROPERTIES

Displays permanent database properties

GLOBAL_NAME

Displays the global database name

V$DATABASE

Contains database information from the control file

2.13 Database Configuration Assistant Command Reference for Silent Mode

This section provides details about the syntax and options for Database Configuration Assistant (DBCA) silent mode commands.

See Also:

Oracle Database 2 Day DBA for more information about DBCA

DBCA Command-Line Syntax and Options Overview

DBCA silent mode has the following command syntax:

dbca  [-silent | -progressOnly] {command options }  | { [command [options]] 
-responseFile response_file_location } [-continueOnNonFatalErrors {true | false}] 
[-h|-help]

Table 2-4 describes the DBCA silent mode options.

Table 2-4 DBCA Silent Mode Options

Option Description

-silent | -progressOnly

Specify -silent to run DBCA in silent mode.

In silent mode, DBCA uses values that you specify, in the response file or as command-line options, to create or modify a database.

Specify -progressOnly to run DBCA in response file mode.

In the response file mode, DBCA uses values that you specify, in the response file or as command line options, to create and configure a database. As it configures and starts the database, it displays a window that contains status messages and a progress bar. DBCA in response file mode uses a graphical display. Ensure that the DISPLAY environment variable is set correctly.

These options are mutually exclusive.

command options

Specify a DBCA command and valid options for the command.

See Table 2-5 for information about DBCA commands.

-responseFile response_file_location

Specify the complete path to the response file. The default name for the response file is dbca.rsp.

-continueOnNonFatalErrors {true | false}

Specify true, the default, for DBCA to continue running if it encounters a nonfatal error.

Specify false for DBCA to stop running if it encounters a nonfatal error.

-h | -help

Displays help for DBCA.

You can display help for a specific command by entering the following:

dbca command -help

For example, to display the help for the -createDatabase command, enter the following:

dbca -createDatabase -help

Table 2-5 describes the DBCA silent mode commands.

Table 2-5 DBCA Silent Mode Commands

Command Description

createDatabase

Creates a database

configureDatabase

Configures a database

createTemplateFromDB

Creates a database template from an existing database

createCloneTemplate

Creates a clone (seed) database template from an existing database

generateScripts

Generates scripts to create a database

deleteDatabase

Deletes a database

createPluggableDatabase

Creates a PDB in a CDB

unplugDatabase

Unplugs a PDB from a CDB

deletePluggableDatabase

Deletes a PDB

configurePluggableDatabase

Configures a PDB

DBCA Templates

You can use DBCA to create a database from a template supplied by Oracle or from a template that you create. A DBCA template is an XML file that contains information required to create a database.

Oracle ships templates for the following two workload types:

  • General purpose OR online transaction processing

  • Data warehouse

Select the template suited to the type of workload your database will support. If you are not sure which to choose, then use the "General purpose OR online transaction processing" template. You can also create custom templates to meet your specific workload requirements.

Note:

The General Purpose or online transaction processing template and the data Warehouse template create a database with the COMPATIBLE initialization parameter set to 12.1.0.2.0.

2.13.1 createDatabase

The createDatabase command creates a database.

Syntax and Parameters

Use the dbca -createDatabase command with the following syntax:

dbca -createDatabase 
    -templateName template_name 
    [-cloneTemplate] 
    -gdbName global_database_name 
    [-sid database_system_identifier]
    [-createAsContainerDatabase {true | false}
        [-numberOfPDBs integer]
        [-pdbName pdb_name]]
    [-sysPassword sys_user_password]
    [-systemPassword system_user_password]
    [-emConfiguration {DBEXPRESS | CENTRAL | BOTH | NONE}
       -dbsnmpPassword DBSNMP_user_password
       [-omsHost EM_management_server_host_name
       -omsPort EM_management_server_port_number
       -emUser EM_admin_username
       -emPassword EM_admin_user_password]]
    [-dvConfiguration {true | false}
        -dvUserName Database_Vault_owner_username
        -dvUserPassword Database_Vault_owner_password
        -dvAccountManagerName Database_Vault_account_manager
        -dvAccountManagerPassword Database_Vault_account_manager_password]
    [-olsConfiguration {true | false}]
    [-datafileDestination directory | -datafileNames text_file_location]
    [-redoLogFileSize integer]
    [-recoveryAreaDestination destination_directory]
    [-datafileJarLocation jar_file_location]
    [-storageType {FS | ASM} 
        [-asmsnmpPassword asmsnmp_password]
        -diskGroupName disk_group_name
        -recoveryGroupName recovery_area_disk_group_name]
    [-characterSet database_character_set]
    [-nationalCharacterSet database_national_character_set]
    [-registerWithDirService {true | false} 
         -dirServiceUserName directory_service_user_name
         -dirServicePassword directory_service_password
         -walletPassword wallet_password]
    [-listeners list_of_listeners]
    [-variablesFile variable_file]
    [-variables variable_list]
    [-initParams parameter_list]
    [-sampleSchema {true | false}]
    [-memoryPercentage integer]
    [-automaticMemoryManagement {true | false}]
    [-totalMemory integer]
    [-databaseType {MULTIPURPOSE | DATA_WAREHOUSING | OLTP}]
    -serviceUserPassword Windows_Oracle_Home_service_user_password

Table 2-6 createDatabase Parameters

Parameter Required/Optional Description

-templateName template_name

Required

Name of an existing template in the default location or the complete path to a template that is not in the default location

-cloneTemplate

Optional

Indicates that the template is a seed template

A seed template contains both the structure and the physical data files of an existing database. When the template file extension is .dbc, DBCA treats it as seed template by default.

-gdbName global_database_name

Required

Global database name in the form database_name.domain_name

-sid database_system_identifier

Optional

Database system identifier

The SID uniquely identifies the instance that runs the database. If it is not specified, then it defaults to the database name.

-createAsContainerDatabase {true | false}

Optional

Specify true to create a CDB.

Specify false, the default, to create a non-CDB.

When true is specified, the following additional parameters are optional:

  • -numberOfPDBs: Number of PDBs to create. The default is 0 (zero).

  • -pdbName: Base name of each PDB. A number is appended to each name if -numberOfPDBs is greater than 1. This parameter must be specified if -numberOfPDBs is greater than 0 (zero).

-sysPassword sys_user_password

Optional

SYS user password for the new database

-systemPassword system_user_password

Optional

SYSTEM user password for the new database

-emConfiguration {DBEXPRESS | CENTRAL | BOTH | NONE}

Optional

When DBEXPRESS, CENTRAL, or BOTH is specified, specify the following additional parameters:

  • -dbsnmpPassword: DBSNMP user password

  • -omsHost: Enterprise Manager management server host name

  • -omsPort: Enterprise Manager management server port number

  • -emUser: Host username for Enterprise Manager administrator

  • -emPassword: Host user password for Enterprise Manager administrator

-dvConfiguration {true | false}

Optional

Specify false, the default, to indicate that the database will not use Oracle Database Vault.

Specify true to configure and enable Database Vault, or specify false to not configure and enable Database Vault.

When true is specified, the following additional Database Vault parameters are required:

  • -dvUserName: Specify the Database Vault owner username.

  • -dvUserPassword: Specify Database Vault owner password.

  • -dvAccountManagerName: Specify a separate Database Vault account manager.

  • -dvAccountManagerPassword: Specify the Database Vault account manager password.

-olsConfiguration {true | false}

Optional

Specify true to configure and enable Oracle Label Security.

Specify false, the default, to indicate that the database will not use Oracle Label Security.

-datafileDestination directory

Optional

Complete path to the location of the database's data files

Note: The -datafileDestination and -datafileNames parameters are mutually exclusive.

-datafileNames text_file_location

Optional

A text file containing database objects such as control files, tablespaces, redo log files, and the SPFILE matched to their corresponding file name mappings in name=value format

Note: The -datafileDestination and -datafileNames parameters are mutually exclusive.

-redoLogFileSize integer

Optional

Size of each online redo log in megabytes

-recoveryAreaDestination directory

Optional

Destination directory for the Fast Recovery Area, which is a backup and recovery area

-datafileJarLocation jar_file_location

Optional

Location of the database offline backup (for clone database creation only)

The data files for the seed database are stored in compressed RMAN backup format in a file with a .dfb extension.

-storageType {FS | ASM}

Optional

FS for file system

When FS is specified, your database files are managed by the file system of your operating system. You specify the directory path where the database files are to be stored using a database template, the -datafileDestination parameter, or the -datafileNames parameter. Oracle Database can create and manage the actual files.

ASM for Oracle Automatic Storage Management (Oracle ASM)

When ASM is specified, your database files are placed in Oracle ASM disk groups. Oracle Database automatically manages database file placement and naming.

When ASM is specified, specify the following additional parameters:

  • -asmsnmpPassword: ASMSNMP password for ASM monitoring. This parameter is optional.

  • -diskGroupName: Database area disk group name. This parameter is required.

  • -recoveryGroupName: Recovery area disk group name. This parameter is required.

-characterSet database_character_set

Optional

Character set of the database

-nationalCharacterSet database_national_character_set

Optional

National character set of the database

-registerWithDirService {true | false}

Optional

Specify true to register with a Lightweight Directory Access Protocol (LDAP) service.

Specify false, the default, to not register with an LDAP service.

When true is specified, the following additional parameters are required:

  • -dirServiceUserName: Username for the LDAP service

  • -dirServicePassword: Password for the LDAP service

  • -walletPassword: Password for the database wallet

-listeners list_of_listeners

Optional

A comma-separated list of listeners for the database

-variablesFile variable_file

Optional

Complete path to the file that contains the variable-value pairs for variables in the database template

-variables variable_list

Optional

A comma-separated list of name=value pairs for the variables in the database template

-initParams parameter_list

Optional

A comma-separated list of name=value pairs of initialization parameter values for the database

-sampleSchema {true | false}

Optional

Specify true to include sample schemas (EXAMPLE tablespace) in your database. Oracle guides and educational materials contain examples based on the sample schemas. Oracle recommends that you include them in your database.

Specify false to create the database without the sample schemas.

-memoryPercentage integer

Optional

The percentage of physical memory that can be used by Oracle Database

-automaticMemoryManagement {true | false}

Optional

Forces the use of the MEMORY_TARGET initialization parameter

-totalMemory integer

Optional

Total amount of physical memory, in megabytes, that can be used by the new database

-databaseType {MULTIPURPOSE | DATA_WAREHOUSING | OLTP}

Optional

Specify MULTIPURPOSE if the database is for both OLTP and data warehouse purposes.

Specify DATA_WAREHOUSING if the primary purpose of the database is a data warehouse.

Specify OLTP if the primary purpose of the database is online transaction processing.

-serviceUserPassword Windows_Oracle_Home_service_user_password

Required

For the Windows platform only, specify the Oracle Home User password if the Oracle Home was installed using an Oracle Home User.

2.13.2 configureDatabase

The configureDatabase command configures a database.

Syntax and Parameters

Use the dbca -configureDatabase command with the following syntax:

dbca -configureDatabase 
   -sourceDB source_database_sid
   [-sysDBAUserName user_name
    -sysDBAPassword password]
   [-registerWithDirService | -unregisterWithDirService | -regenerateDBPassword {true | false}
      -dirServiceUserName directory_service_user_name
      -dirServicePassword directory_service_password
      -walletPassword wallet_password]
   [-addDBOption options_list]
   [-dvConfiguration {true | false}
      -dvUserName Database_Vault_owner_username
      -dvUserPassword Database_Vault_owner_password
      -dvAccountManagerName Database_Vault_account_manager
      -dvAccountManagerPassword Database_Vault_account_manager_password]

Table 2-7 configureDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier of the database being configured

-sysDBAUserName user_name

Optional

Username of a user that has SYSDBA administrative privilege

-sysDBAPassword password

Optional

Password of the user granted SYSDBA administrative privilege

-registerWithDirService | -unregisterWithDirService | -regenerateDBPassword {true | false}

Optional

Set one of the following parameters to either true or false:

  • -registerWithDirService: true registers with a Lightweight Directory Access Protocol (LDAP) service; false, the default, does not register with an LDAP service.

  • -unregisterWithDirService: true unregisters from an LDAP service; false, the default, does not unregister from an LDAP service.

  • -regenerateDBPassword: true regenerates the database password for an LDAP service; false, the default, does not regenerate the database password for an LDAP service.

When true is specified, the following additional parameters are required:

  • -dirServiceUserName: Username for the LDAP service

  • -dirServicePassword: Password for the LDAP service

  • -walletPassword: Password for the database wallet

-addDBOption

Optional

Specify any of the following Oracle Database options in a comma separated list:

  • JSERVER

  • ORACLE_TEXT

  • IMEDIA

  • CWMLITE

  • SPATIAL

  • OMS

  • APEX

  • DV

-dvConfiguration {true | false}

Optional

Specify false, the default, to indicate that the database will not use Oracle Database Vault.

Specify true to configure and enable Database Vault, or specify false to not configure and enable Database Vault.

When true is specified, the following additional Database Vault parameters are required:

  • -dvUserName: Specify the Database Vault owner username.

  • -dvUserPassword: Specify Database Vault owner password.

  • -dvAccountManagerName: Specify a separate Database Vault account manager.

  • -dvAccountManagerPassword: Specify the Database Vault account manager password.

2.13.3 createTemplateFromDB

The createTemplateFromDB command creates a database template from an existing database.

Syntax and Parameters

Use the dbca -createTemplateFromDB command with the following syntax:

dbca -createTemplateFromDB 
   -sourceDB source_database_sid
   -templateName new_template_name
   -sysDBAUserName user_name
   -sysDBAPassword password
   [-maintainFileLocations {true | false}]
   [-connectionString easy_connect_string]

Table 2-8 createTemplateFromDB Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier

-templateName new_template_name

Required

Name of the new database template

-sysDBAUserName user_name

Required

Username of a user that has SYSDBA administrative privilege

-sysDBAPassword password

Required

Password of the user granted SYSDBA administrative privilege

-maintainFileLocations {true | false}

Optional

Specify true to use the file locations of the database in the template.

Specify false, the default, to use different file locations in the template. The file locations are determined by Oracle Flexible Architecture (OFA).

-connectionString easy_connect_string

Optional

Easy connect string for connecting to a remote database in the following form:

"host[:port][/service_name][:server][/instance_name]"

2.13.4 createCloneTemplate

The createCloneTemplate command creates a clone (seed) database template from an existing database.

Syntax and Parameters

Use the dbca -createCloneTemplate command with the following syntax:

dbca -createCloneTemplate 
   -sourceSID source_database_sid
   -templateName new_template_name
   [-sysDBAUserName user_name
    -sysDBAPassword password]
   [-maxBackupSetSizeInMB integer]
   [-rmanParallelism integer
   [-datafileJarLocation jar_location]

Table 2-9 createCloneTemplate Parameters

Parameter Required/Optional Description

-sourceSID source_database_sid

Required

The database system identifier

-templateName new_template_name

Required

Name of the new database template

-sysDBAUserName user_name

Optional

Username of a user granted SYSDBA administrative privilege

-sysDBAPassword password

Optional

Password of the user granted SYSDBA administrative privilege

-maxBackupSetSizeInMB integer

Optional

Maximum backup set size in megabytes

-rmanParallelism integer

Optional

Parallelism for Recovery Manager (RMAN) operations

-datafileJarLocation jar_location

Optional

Complete path that specifies where to place data files in a compressed format

2.13.5 generateScripts

The generateScripts command generates scripts to create a database.

Syntax and Parameters

Use the dbca -generateScripts command with the following syntax:

dbca -generateScripts 
   -templateName template_name
   -gdbName global_database_name
   [-scriptDest script_destination]

Table 2-10 generateScripts Parameters

Parameter Required/Optional Description

-templateName template_name

Required

Name of an existing database template in the default location or the complete path of a template that is not in the default location

-gdbName global_database_name

Required

Global database name in the form database_name.domain_name

-scriptDest script_destination

Optional

Complete path that specifies where to place the scripts

2.13.6 deleteDatabase

The deleteDatabase command deletes a database.

Syntax and Parameters

Use the dbca -deleteDatabase command with the following syntax:

dbca -deleteDatabase 
   -sourceDB source_database_sid
   [-sysDBAUserName user_name
    -sysDBAPassword password]
   [-emConfiguration {DBEXPRESS | CENTRAL | BOTH | NONE}
     [-omsHost central_agent_home
      -omsPort central_agent_port
      -emUser host_username
      -emPassword host_user_password]]

Table 2-11 deleteDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier

-sysDBAUserName user_name

Optional

Username of a user that has SYSDBA administrative privilege

-sysDBAPassword password

Optional

Password of the user granted SYSDBA administrative privilege

-emConfiguration {DBEXPRESS | CENTRAL | BOTH | NONE}

Optional

When DBEXPRESS, CENTRAL, or BOTH is specified, specify the following additional parameters:

  • -omsHost: Enterprise Manager central agent home

  • -omsPort: Enterprise Manager central agent port

  • -emUser: Host username for Enterprise Manager backup jobs

  • -emPassword: Host user password for Enterprise Manager backup jobs

2.13.7 createPluggableDatabase

The createPluggableDatabase command creates a PDB in a CDB.

Syntax and Parameters

Use the dbca -createPluggableDatabase command with the following syntax:

dbca -createPluggableDatabase 
   -sourceDB source_database_sid
   -pdbName new_pdb_name
   [-createAsClone {true | false}]
   [-createPDBFrom {DEFAULT | FILEARCHIVE | RMANBACKUP | USINGXML}
      [-pdbArchiveFile pdb_archive_file_location]
      [-PDBBackUpfile pdb_backup_file_location]
      [-PDBMetadataFile pdb_metadata_file_location]
      [-pdbAdminUserName pdb_admin_user_name]
      [-pdbAdminPassword pdb_admin_password]
      [-createNewPDBAdminUser {true | false}]
      [-sourceFileNameConvert source_file_name_convert_clause]
      [-fileNameConvert file_name_convert_clause]
      [-copyPDBFiles  {true | false}]]
   [-pdbDatafileDestination pdb_datafile_destination]
   [-useMetaDataFileLocation {true | false}]
   [-registerWithDirService {true | false} 
      -dirServiceUserName directory_service_user_name
      -dirServicePassword directory_service_password
      -walletPassword wallet_password]
   [-lbacsysPassword LBACSYS_user_password]
   [-createUserTableSpace {true | false)]
   [-dvConfiguration {true | false}
      -dvUserName Database_Vault_owner_username
      -dvUserPassword Database_Vault_owner_password
      -dvAccountManagerName Database_Vault_account_manager
      -dvAccountManagerPassword Database_Vault_account_manager_password]

Table 2-12 createPluggableDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier of the CDB

-pdbName new_pdb_name

Required

Name of the new PDB

-createAsClone {true | false}

Optional

Specify TRUE if the files you plan to use to create the new PDB are the same files that were used to create an existing PDB. Specifying TRUE ensures that Oracle Database generates unique PDB DBID, GUID, and other identifiers expected for the new PDB.

Specify FALSE, the default, if the files you plan to use to create the new PDB are not the same files that were used to create an existing PDB.

-createPDBFrom {DEFAULT | FILEARCHIVE | RMANBACKUP | USINGXML}

Optional

Specify DEFAULT to create the PDB from the CDB's seed. When you specify DEFAULT, the following additional parameters are required:

  • -pdbAdminUserName: The username of the PDB's local administrator

  • -pdbAdminPassword: The password for the PDB's local administrator

Specify FILEARCHIVE to create the PDB from an unplugged PDB's files. When you specify FILEARCHIVE, the following additional parameter is required:

  • -pdbArchiveFile: Complete path and name for unplugged PDB's archive file

    The archive file contains all of the files for the PDB, including its XML metadata file and its data files. Typically, the archive file has a .gz extension.

  • -createNewPDBAdminUser: Specify true to create a new PDB administrator or false to avoid creating a new PDB administrator.

Specify RMANBACKUP to create the PDB from a Recovery Manager (RMAN) backup. When you specify RMANBACKUP, the following additional parameters are required:

  • -PDBBackUpfile: Complete path and name for the PDB backup file

  • -PDBMetadataFile: Complete path and name for the PDB's XML metadata file

Specify USINGXML to create the PDB from an unplugged PDB's XML metadata file. When you specify USINGXML, the following additional parameter is required:

  • -PDBMetadataFile: Complete path and name for the PDB's XML metadata file

Specify these other clauses if they are required:

  • -sourceFileNameConvert: The SOURCE_FILE_NAME_CONVERT clause.

  • -fileNameConvert: The FILE_NAME_CONVERT clause.

  • -copyPDBFiles: Specify true for the FILE_NAME_CONVERT clause to copy the files, or specify false if the files do not need to be copied.

See "The CREATE PLUGGABLE DATABASE Statement" for more information about these clauses.

-pdbDatafileDestination pdb_datafile_destination

Optional

Compete path for the location of the new PDB's data files

When this parameter is not specified, either Oracle Managed Files or the PDB_FILE_NAME_CONVERT initialization parameter specifies how to generate the names and locations of the files. If you use both Oracle Managed Files and the PDB_FILE_NAME_CONVERT initialization parameter, then Oracle Managed Files takes precedence.

When this parameter is not specified, Oracle Managed Files is not enabled, and the PDB_FILE_NAME_CONVERT initialization parameter is not set, by default a path to a subdirectory with the name of the PDB in the directory for the root's files is used.

-useMetaDataFileLocation {true | false}

Optional

Specify true to use the data file path defined in XML metadata file within a PDB archive when extracting data files

Specify false, the default, to not use the data file path defined in XML metadata file within a PDB archive when extracting data files

-registerWithDirService {true | false}

Optional

Specify true to register with a Lightweight Directory Access Protocol (LDAP) service.

Specify false, the default, to not register with an LDAP service.

When true is specified, the following additional parameters are required:

  • -dirServiceUserName: Username for the LDAP service

  • -dirServicePassword: Password for the LDAP service

  • -walletPassword: Password for the database wallet

-lbacsysPassword

Optional

Specify the LBACSYS user password when configuring Oracle Label Security. This parameter is required when configuring Oracle Label Security.

-dvConfiguration {true | false}

Optional

Specify false, the default, to indicate that the PDB will not use Oracle Database Vault.

Specify true to configure and enable Database Vault.

When true is specified, the following additional Database Vault parameters are required:

  • -dvUserName: Specify the Database Vault owner username.

  • -dvUserPassword: Specify Database Vault owner password.

  • -dvAccountManagerName: Specify a separate Database Vault account manager.

  • -dvAccountManagerPassword: Specify the Database Vault account manager password.

2.13.8 unplugDatabase

The unplugDatabase command unplugs a PDB from a CDB.

Syntax and Parameters

Use the dbca -unplugDatabase command with the following syntax:

dbca -unplugDatabase 
   -sourceDB source_database_sid
   -pdbName pdb_name
      [-pdbArchiveFile pdb_archive_file_location]
      [-PDBBackUpfile pdb_backup_file_location]
      [-PDBMetadataFile pdb_metadata_file_location]
      [-archiveType {TAR | RMAN | NONE}]
   [-unregisterWithDirService {true | false}
      -dirServiceUserName directory_service_user_name
      -dirServicePassword directory_service_password
      -walletPassword wallet_password]

Table 2-13 unplugDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier of the CDB

-pdbName pdb_name

Required

Name of the PDB

-pdbArchiveFile pdb_archive_file_location

Optional

Complete path and file name for the unplugged PDB's archive file

-PDBBackUpFile pdb_archive_file_location

Optional

Complete path and file name for the unplugged PDB's backup file, required when archive type is RMAN

-PDBMetadataFile pdb_archive_file_location

Optional

Complete path and file name for the unplugged PDB's metadata file, required when archive type is RMAN or NONE

-archiveType {TAR | RMAN | NONE}

Optional

Specify TAR to store the unplugged PDB's files in a tar file.

Specify RMAN to store the unplugged PDB's files in an RMAN backup.

Specify NONE to store the unplugged PDB's files without using a tar file or an RMAN backup

-unregisterWithDirService {true | false}

Optional

When true is specified, unregisters from an LDAP service. When false, the default, is specified, does not unregister from an LDAP service.

When true is specified, the following additional parameters are required:

  • -dirServiceUserName: Username for the LDAP service

  • -dirServicePassword: Password for the LDAP service

  • -walletPassword: Password for the database wallet

2.13.9 deletePluggableDatabase

The deletePluggableDatabase command deletes a PDB.

Syntax and Parameters

Use the dbca -deletePluggableDatabase command with the following syntax:

dbca -deletePluggableDatabase 
   -sourceDB source_database_sid
   -pdbName pdb_name

Table 2-14 deletePluggableDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier of the CDB

-pdbName pdb_name

Required

Name of the PDB

2.13.10 configurePluggableDatabase

The configurePluggableDatabase command configures a PDB.

Syntax and Parameters

Use the dbca -configurePluggableDatabase command with the following syntax:

dbca -configurePluggableDatabase 
   -sourceDB source_database_sid
   -pdbName new_pdb_name
   [-dvConfiguration {true | false}
      -dvUserName Database_Vault_owner_username
      -dvUserPassword Database_Vault_owner_password
      -dvAccountManagerName Database_Vault_account_manager
      -dvAccountManagerPassword Database_Vault_account_manager_password]
   [-olsConfiguration {true | false}]
   [-registerWithDirService {true | false} | -unregisterWithDirService {true | false}
      -dirServiceUserName directory_service_user_name
      -dirServicePassword directory_service_password
      -walletPassword wallet_password]
   [-lbacsysPassword LBACSYS_user_password]

Table 2-15 configurePluggableDatabase Parameters

Parameter Required/Optional Description

-sourceDB source_database_sid

Required

The database system identifier of the CDB

-pdbName new_pdb_name

Required

Name of the PDB

-dvConfiguration {true | false}

Optional

Specify false, the default, to indicate that the PDB will not use Oracle Database Vault.

Specify true to configure and enable Database Vault.

When true is specified, the following additional Database Vault parameters are required:

  • -dvUserName: Specify the Database Vault owner username.

  • -dvUserPassword: Specify Database Vault owner password.

  • -dvAccountManagerName: Specify a separate Database Vault account manager.

  • -dvAccountManagerPassword: Specify the Database Vault account manager password.

-olsConfiguration {true | false}

Optional

Specify true to configure and enable Oracle Label Security.

Specify false, the default, to indicate that the PDB will not use Oracle Label Security.

-registerWithDirService {true | false} | -unregisterWithDirService {true | false}

Optional

Specify true to register with a Lightweight Directory Access Protocol (LDAP) service.

Specify false, the default, to unregister from an LDAP service.

When true is specified, the following additional parameters are required:

  • -dirServiceUserName: Username for the LDAP service

  • -dirServicePassword: Password for the LDAP service

  • -walletPassword: Password for the database wallet

-lbacsysPassword

Optional

Specify the LBACSYS user password when configuring Oracle Label Security. This parameter is required when configuring Oracle Label Security.