6 Creating a PDB from Scratch

Use the CREATE PLUGGABLE DATABASE statement to create a PDB in a CDB using the files of the PDB seed (PDB$SEED).

You can also use this statement to create an application PDB in an application container using the files of an application seed or the PDB seed.

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Oracle Database SQL Language Reference for more information about the CREATE PLUGGABLE DATABASE statement

6.1 About Creating a PDB from Scratch

Use the CREATE PLUGGABLE DATABASE statement to create a new PDB by using the files of the PDB seed or an application PDB from the files of an application seed or the PDB seed.

The statement copies these files to a new location and associates them with the new PDB. The following figure illustrates how this technique creates a new PDB in a CDB with the CDB root as the current container.

Figure 6-1 Create a PDB in the CDB Root Using the PDB$SEED Files

Description of Figure 6-1 follows
Description of "Figure 6-1 Create a PDB in the CDB Root Using the PDB$SEED Files"

The following figure illustrates how this technique creates a new application PDB in an application container with the application root as the current container.

Figure 6-2 Create a PDB in an Application Root Using the Application Seed Files

Description of Figure 6-2 follows
Description of "Figure 6-2 Create a PDB in an Application Root Using the Application Seed Files"

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When an application container includes an application seed, and a CREATE PLUGGABLE DATABASE statement is run in the application root to create an application PDB from the seed, the application PDB is created using the application seed. However, when an application container does not include an application seed, and a CREATE PLUGGABLE DATABASE statement is run in the application root to create an application PDB from the seed, the application PDB is created using the PDB seed (PDB$SEED ).

When you create a new PDB or application PDB from the seed, you must specify an administrator for the PDB or application PDB in the CREATE PLUGGABLE DATABASE statement. The statement creates the administrator as a local user in the PDB and grants the PDB_DBA role locally to the administrator.

Before creating a PDB using the PDB seed or an application seed, address the questions that apply to creating a PDB from the seed in Table 5-3. The table describes which CREATE PLUGGABLE DATABASE clauses you must specify based on different factors.

6.2 Creating a PDB

Using the CREATE PLUGGABLE DATABASE statement, you can create a PDB from the PDB seed, and you can create an application PDB from an application seed or the PDB seed.

Prerequisites

Before creating a PDB from the PDB seed (PDB$SEED) or an application PDB from an application seed or the PDB seed, complete the prerequisites described in "General Prerequisites for PDB Creation".

To create a PDB:

  1. In SQL*Plus, ensure that the current container is the CDB root or an application root.

    When the current container is the CDB root, the PDB is created in the CDB using the files of the PDB seed.

    When the current container is an application root, the application PDB is created in the application container using the files of the application seed. If there is no application seed in the application container, then the application PDB is created in the application container using the files of the PDB seed.

  2. Run the CREATE PLUGGABLE DATABASE statement, and specify a local administrator for the PDB. Specify other clauses when they are required.

    After you create the PDB, it is in mounted mode, and its status is NEW. You can view the open mode of a PDB by querying the OPEN_MODE column in the V$PDBS view. You can view the status of a PDB by querying the STATUS column of the CDB_PDBS or DBA_PDBS view.

    A new default service is created for the PDB. The service has the same name as the PDB and can be used to access the PDB. Oracle Net Services must be configured properly for clients to access this service.

  3. Open the new PDB in read/write mode.

    You must open the new PDB in read/write mode for Oracle Database to complete the integration of the new PDB into the CDB. An error is returned if you attempt to open the PDB in read-only mode. After the PDB is opened in read/write mode, its status is NORMAL.

  4. Back up the PDB.

    A PDB cannot be recovered unless it is backed up.

A local user with the name of the specified local administrator is created and granted the PDB_DBA common role locally in the PDB. If this user was not granted administrator privileges during PDB creation, then use the SYS and SYSTEM common users to administer to the PDB.

Note:

If an error is returned during PDB creation, then the PDB being created might be in an UNUSABLE state. You can check a PDB's state by querying the CDB_PDBS or DBA_PDBS view, and you can learn more about PDB creation errors by checking the alert log. An unusable PDB can only be dropped, and it must be dropped before a PDB with the same name as the unusable PDB can be created.

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6.3 Creating a PDB: Examples

These examples create a new PDB named salespdb and a salesadm local administrator given different factors.

In addition to creating the salespdb PDB, this statement grants the PDB_DBA role to the PDB administrator salesadm and grants the specified predefined Oracle roles to the PDB_DBA role locally in the PDB.

In each example, the root to which the new PDB belongs depends on the current container when the CREATE PLUGGABLE DATABASE statement is run:

  • When the current container is the CDB root, the new PDB is created in the CDB root.

  • When the current container is an application root in an application container, the new PDB is created as an application PDB in the application root.

6.3.1 Creating a PDB Using No Clauses: Example

This example shows the simplest way to create a PDB.

This example assumes the following factors:

  • Storage limits are not required for the PDB. Therefore, the STORAGE clause is not required.

  • The PDB does not require a default tablespace.

  • The PATH_PREFIX clause is not required.

  • The FILE_NAME_CONVERT clause and the CREATE_FILE_DEST clause are not required.

    Either Oracle Managed Files is enabled for the CDB, or the PDB_FILE_NAME_CONVERT initialization parameter is set. The files associated with the PDB seed or application seed will be copied to a new location based on the Oracle Managed Files configuration or the initialization parameter setting.

  • There is no file with the same name as the new temp file that will be created in the target location. Therefore, the TEMPFILE REUSE clause is not required.

  • No predefined Oracle roles need to be granted to the PDB_DBA role.

The following statement creates the PDB:

CREATE PLUGGABLE DATABASE salespdb ADMIN USER salesadm IDENTIFIED BY pwd;

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6.3.2 Creating a PDB and Granting Predefined Oracle Roles to the PDB Administrator: Example

This example uses the ROLES parameter to grant a predefined role.

This example assumes the following factors:

  • Storage limits are not required for the PDB. Therefore, the STORAGE clause is not required.

  • The PDB does not require a default tablespace.

  • The PATH_PREFIX clause is not required.

  • The FILE_NAME_CONVERT clause and the CREATE_FILE_DEST clause are not required.

    Either Oracle Managed Files is enabled, or the PDB_FILE_NAME_CONVERT initialization parameter is set. The files associated with the PDB seed or application seed will be copied to a new location based on the Oracle Managed Files configuration or the initialization parameter setting.

  • There is no file with the same name as the new temp file that will be created in the target location. Therefore, the TEMPFILE REUSE clause is not required.

  • The PDB_DBA role should be granted the following predefined Oracle role locally: DBA.

The following statement creates the PDB:

CREATE PLUGGABLE DATABASE salespdb 
  ADMIN USER salesadm IDENTIFIED BY password
    ROLES=(DBA);

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6.3.3 Creating a PDB Using Multiple Clauses: Example

This example creating a PDB using the STORAGE, DEFAULT TABLESPACE, PATH_PREFIX, and FILE_NAME_CONVERT clauses.

This example assumes the following factors:

  • Storage limits must be enforced for the PDB. Therefore, the STORAGE clause is required. Specifically, all tablespaces that belong to the PDB must not exceed 2 gigabytes.

  • A default permanent tablespace is required for any non-administrative users for which you do not specify a different permanent tablespace. Specifically, this example creates a default permanent tablespace named sales with the following characteristics:

    • The single data file for the tablespace is sales01.dbf, and the statement creates it in the /disk1/oracle/dbs/salespdb directory.

    • The SIZE clause specifies that the initial size of the tablespace is 250 megabytes.

    • The AUTOEXTEND clause enables automatic extension for the file.

  • The path prefix must be added to the PDB directory object paths. Therefore, the PATH_PREFIX clause is required. In this example, the path prefix /disk1/oracle/dbs/salespdb/ is added to the PDB’s directory object paths.

  • The CREATE_FILE_DEST clause will not be used, Oracle Managed Files is not enabled, and the PDB_FILE_NAME_CONVERT initialization parameter is not set. Therefore, the FILE_NAME_CONVERT clause is required. Specify the location of the data files for the PDB seed or application seed on your system. In this example, Oracle Database copies the files from /disk1/oracle/dbs/pdbseed to /disk1/oracle/dbs/salespdb.

  • There is no file with the same name as the new temp file that will be created in the target location. Therefore, the TEMPFILE REUSE clause is not required.

  • No predefined Oracle roles need to be granted to the PDB_DBA role.

The following statement creates the PDB:

CREATE PLUGGABLE DATABASE salespdb 
  ADMIN USER salesadm IDENTIFIED BY password
  STORAGE (MAXSIZE 2G)
  DEFAULT TABLESPACE sales 
    DATAFILE '/disk1/oracle/dbs/salespdb/sales01.dbf' SIZE 250M 
    AUTOEXTEND ON
    PATH_PREFIX = '/disk1/oracle/dbs/salespdb/'
    FILE_NAME_CONVERT = ('/disk1/oracle/dbs/pdbseed/', 
                         '/disk1/oracle/dbs/salespdb/');

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