UPGRADING TO ORACLE DATABASE 10g in Font

Creation Quick Response Code in Font UPGRADING TO ORACLE DATABASE 10g

In the past, the upgrade process required you to run various scripts throughout the process, but the Oracle Database 10g upgrade process only requires a single upgrade script (there s an example of the use of this script in the Upgrading Manually section later).

If you use the manual upgrade process, you must perform due diligence: this means removing or changing all your obsolete initialization parameters and running all the Oracle-provided database upgrade scripts. This method s advantage is that you control the whole upgrade process. There are drawbacks to the manual method, however: you must back up the database yourself, you must use the correct initialization parameters, and you must give the System tablespace adequate free space.

The old Export and Import utilities are still available, should you wish to use them, though they've been supplanted by the Data Pump Export and Import utilities. They are still pretty useful if you have a very small database.

The Database Upgrade Assistant (DBUA)

If you use the DBUA, it does the preinstallation checks for you and automatically manages the upgrade process by performing the following tasks: Performs initialization checks, including for invalid data types, unsupported character sets, invalid user accounts, and sufficient free space in the tablespaces Backs up the database Creates any necessary objects Invokes the correct upgrade script Shows the progress of the upgrade process Creates the parameter and listener files in the new Oracle home

Before you start an upgrade, you have to check your system for any necessary changes. Luckily, we have the Pre-Upgrade Information Tool, which does this for us. The Pre-Upgrade Information Tool, which is implemented by executing an Oracle-supplied script, helps you collect various critical pieces of information before the upgrade process begins. Too often in the past, DBAs have needed to restart the upgrade process because of initialization features that were incompatible or tablespace sizes that were too small, and this new tool helps avoid that situation.

The manual process and the DBUA both use the same Pre-Upgrade Information Tool. The DBUA automatically runs it as part of this initial check.

The Pre-Upgrade Information Tool provides information about the following: The Sysaux tablespace: Before you run the upgrade script, you have to create the Sysaux tablespace. The Pre-Upgrade Information Tool will recommend the correct settings for this. Log files: The new version of Oracle needs redo log files to be at least 4MB. If your existing log files are smaller than this, the Pre-Upgrade Information Tool will tell you to increase their size. Tablespace sizes: If your existing tablespaces lack the free space required, the Pre-Upgrade Information Tool will tell you so you can increase their size. Initialization parameters: The Pre-Upgrade Information Tool tells you which initialization parameters you should remove (because they are deprecated and obsolete) and which you should add before you can upgrade. Database versions and compatibility level: The Pre-Upgrade Information Tool lets you know whether you need to change the compatibility level of your database with the COMPATIBLE initialization parameter. Time estimates: The Pre-Upgrade Information Tool will give you an estimate of how long the upgrade will take. The Pre-Upgrade Information Tool will do a lot of the work for you. Just make sure that you implement the recommended changes and you will be ready to upgrade to Oracle Database 10g. The Pre-Upgrade Information Tool is actually a SQL script, called utlu102i.sql (in $ORACLE_ HOME/rdbms/admin). Here s how you invoke the Pre-Upgrade Information Tool: SQL> @ $ORACLE_HOME/rdbms/admin/utlu102i.sql Oracle Database 10.2 Upgrade Information Tool 02-20-2005 16:45:48 Database: ----------> name: FINANCE --> version: 8.1.7.0.0 --> compatibility: 8.1.0 WARNING: Database compatibility must be set to 9.2.0 prior to upgrade. . . . PL/SQL procedure successfully completed. SQL>