Oracle Database 11 g - Online Public Access Catalog

18 CHAPTER 1 ■ INSTALLING, UPGRADING, AND MANAGING CHANGEutlu111i.sql and utlu111s.sql scripts, the improvements are common to both methods. Thepre-upgrade and the post-upgrade scripts in Oracle 11g work the same way as they did in theOracle 10g version.Upgrading and the Compatibility FactorThe default compatibility value for Oracle Database 11g version 11.1 is 11.1. However, you canupgrade to Oracle Database 11g with a minimum compatibility value of 10.0.0. Before youperform the database upgrade, you must set the compatibility level for your new database bysetting a value for the initialization parameter compatible. If you omit this parameter altogetherfrom the new initialization parameter file, it defaults to 11.1.0. Oracle recommends you use theminimum value for the compatible parameter during the upgrade (10.0.0). This way, if yourupgrade doesn’t go well for some reason and you have to back out of the upgrade process, theupgraded database won’t become incompatible with your previous (10g.x) release.If you upgrade to 11.1 and keep the compatible parameter at 10.0.0.0, only a small portionof the new features, limited to those that don’t make incompatible database structures on disk,will be allowed. The vast majority of the 11g features will make these permanent changes, however,so the lower compatibility level disables those new features. Once you confirm that the upgradedid finish successfully, you can change the value of the compatible parameter to 11.1 or greater,depending on the software release you installed. Just remember that once you do this andrestart the database, you can’t downgrade to the previous release.Before you increase the setting of the compatible initialization parameter, back up thedatabase, and either edit the initialization parameter (compatible=11.1.0, for example) or, ifyou’re using the server parameter file, use the following statement to make the change:SQL> alter system set compatible ='11.1.0' scope=spfile;Once you change the value of the compatible parameter, shut down the database(shutdown immediate), and restart it with the startup command. To go back to the old compatibilitylevel after this if something doesn’t work right, you must return to the backup you madeof the pre-upgrade database.Upgrade Path to Oracle 11gWhether you can directly upgrade your current Oracle database to Oracle 11g or have to perform anupgrade to an intermediate release first depends on your current Oracle database release. Oraclesupports a direct upgrade to Oracle Database 11g Release 1, if you’re migrating from a 9.2.04 ornewer release of the Oracle database software. If you want to upgrade to Oracle Clusterware 11grelease 1 (11.1), then you must upgrade from an Oracle Clusterware release 10.2.0.3 or newer.Here’s a summary of the upgrade path to Oracle 11g for Oracle database releases older than 9.2.04.• 7.3.3 (or lower) ➤ 7.3.4 ➤ 9.2.0.8 ➤ 11.1• 8.0.5 (or lower) ➤ 8.0.6 ➤ 9.2.0.8 ➤ 11.1• 8.1.7 (or lower) ➤ 8.1.7.4 ➤ 9.2.0.8 ➤ 11.1• 9.0.1.3 (or lower) ➤ 9.0.1.4 ➤ 9.2.0.8 ➤ 11.1• 9.2.0.3 (or lower) ➤ 9.2.0.8 ➤ 11.1