1 Understanding the Upgrade Process

This chapter provides an overview of upgrading Oracle Database Express Edition to Oracle Database 10g release 2 (10.2.0.3).

This chapter contains the following topics:

• Overview of the Upgrade Process

• Backing Up Your Database

• Restoring Your Database

• Migrating Data to a Different Operating System

• Downgrading Back to Oracle Database Express Edition

• Understanding the Oracle Home Directory

• System Requirements

1.1 Overview of the Upgrade Process

The process of upgrading Oracle Database Express Edition to Oracle Database 10g involves the following steps:

1. Determine how you want to back up your existing database. See "Backing Up Your Database".

2. Perform the tasks involved in the upgrade process. See "Upgrading the Software" .

3. Perform the necessary post-upgrade tasks. See "Post-UpgradeTasks Specific to Oracle Application Express".

4. Review key differences between Oracle Database Express Edition and Oracle Database 10g. See "What's Different in Your New Database".

5. Test the upgraded database by logging in to Oracle Application Express. See "Logging In to Oracle Application Express".

1.1.1 About the Upgrade Task

Within the overall process just described, you perform the actual upgrade by running the Database Upgrade Assistant from the Oracle Database 10g Release 2 Oracle home. This tool steps you through the upgrade process and configures the database for the new Oracle Database 10g release 10.2.0.3.

Running Database Upgrade Assistant and upgrading your database consists of the following steps:

1. Start Database Upgrade Assistant from the 10.2.0.3 Oracle home.

2. Select the XE database.

   Database Upgrade Assistant performs pre-upgrade checks.

3. Rename the database by entering a new Global Database Name and Oracle system identifier (SID).

4. Specify target locations for database files.

5. Configure the Flash Recovery Area.

6. Optionally, recompile invalid objects.

7. Optionally, back up your database.

8. Specify database management options.

9. Specify a database account password and an Oracle Application Express administrator password.

   Database Upgrade Assistant shuts down the Oracle Database Express Edition database, renames the database instance, moves the database files to the new location, and re-creates the Temp files. Note that once these tasks are complete, the database files exist in the new location.

See Also:

Chapter 2, "Upgrading the Software" for a more detailed explanation of the upgrade process

1.2 Backing Up Your Database

A backup is a copy of data from your database that you can use to reconstruct that data. Oracle recommends that you back up your database before upgrading. If errors occur during the upgrade, then you may have to restore the database from the backup.

You can back up your database before you upgrade, or you can have Database Upgrade Assistant back it up while you upgrade. If you select this latter option, then Database Upgrade Assistant makes a copy of all your database files in the directory you specify in the Backup Directory field. Database Upgrade Assistant performs this cold backup automatically after it shuts down the database, but before it begins performing the upgrade procedure.

Database Upgrade Assistant also creates a script file that you can use to restore the database files.

See Also:

"Backing Up and Recovering" in Oracle Database Express Edition 2 Day DBA for information about how to back up your database before upgrading

1.3 Restoring Your Database

If errors occur during the upgrade process, then you can restore Oracle Database Express Edition database by performing one of the following steps:

• Click Restore Database on the Summary page.

• Run the script created by the Database Upgrade Assistant from the command prompt:

  • On Windows, the script file is called db_name_restore.bat

  • On Linux, the script file is called db_name_restore.sh

Note:

You must stop Enterprise Manager Database Control after running the restore script by using the emctl stop dbconsole command from the command prompt.

1.4 Migrating Data to a Different Operating System

When using Database Upgrade Assistant, you cannot migrate data in a database on one operating system to a database on another operating system.

If you want to migrate Oracle Database to a different operating system, then the recommended best practice is as follows:

1. Upgrade to the latest Oracle Database release on the current operating system by following the instructions in this guide.

2. Use the Oracle Database cross-platform transportable tablespace feature or the Oracle Data Pump Export and Import utilities to migrate the upgraded database to the new operating system.

See Also:

Oracle Database Utilities for information about the utilities bundled with the Oracle Database, including Export, Import, and SQL*Loader

1.5 Downgrading Back to Oracle Database Express Edition

Once you have upgraded to Oracle Database 10g, you cannot downgrade back to Oracle Database Express Edition.

1.6 Understanding the Oracle Home Directory

The Oracle home (ORACLE_HOME) directory is where you choose to install the software for a particular Oracle product. You must install different Oracle products, or different releases of the same Oracle product, in separate Oracle home directories. This means that Oracle Database Express Edition and Oracle Database 10g must be installed in separate Oracle homes. When you run Oracle Universal Installer, it prompts you to specify the path to this directory, as well as a name that identifies it.

On Windows, the default Oracle home directory for Oracle Database 10g release 2 is db_1. The full path is x:\oracle\product\10.2.0\db_1

On Linux, Oracle recommends that you specify a path similar to the following for the Oracle home directory:

/u01/app/oracle/product/10.2.0/db_1

1.7 System Requirements

For hardware and software system requirements, see the Oracle Database Installation Guide for your operating system. Note that during the upgrade process, the installer verifies that your system meets these minimum requirements.