The new release of Oracle Database provides improvements to upgrade performance, automation, and reporting.
This preface includes these topics:
Oracle Database 12c includes many new features, some of which directly affect upgrading. The following features are new for the upgrade process.
See Also:Oracle Database New Features Guide for a complete description of the new features in Oracle Database 12c
A new Pre-Upgrade Information Tool has been created for Oracle Database 12c. This new utility provides fixup scripts to address issues that might be present both before and after the upgrade. Database Upgrade Assistant (DBUA) and the Pre-Upgrade Information Tool perform detailed checks of the database to be upgraded, and the special scripts are generated specifically to fix any problems that are found.
During the pre-upgrade phase, you can interactively run fixup scripts to resolve issues that are found. Post-upgrade fixup scripts are generated depending on the results of the upgrade process. DBUA prompts you to run the appropriate scripts as critical issues are found.
In Oracle Database 12c, the
catupgrd.sql Upgrade Utility has been replaced with the
catctl.pl Parallel Upgrade Utility. You can run upgrade scripts and processes in parallel, taking full advantage of CPU capacity and shortening the upgrade time. You can choose to upgrade your database in parallel or serial mode. In earlier releases, only serial mode was available, which meant that the upgrade scripts and processes ran one after the other, regardless of how much CPU capacity was available.
Database Upgrade Assistant (DBUA) takes full advantage of the Parallel Upgrade Utility, and by default DBUA runs in parallel upgrade mode. Parallel processing decreases the time for the database upgrade by optimally utilizing the CPU power of the system in which the database resides.
In this release, there are more options for recovering from failures during upgrade and for restarting the upgrade from the point where the failure occurred. For example, Oracle Database 12c introduces Oracle Recovery Manager (RMAN) support and Guaranteed Restore Point features. You can fix a problem that DBUA encounters and then return to the upgrade process.
With achievement logging that tracks the upgrade progress, you now have the option to use Guaranteed Restore Point to restore your database if the upgrade fails. DBUA automatically creates a Restore Point.
If an error occurs while DBUA during pre-upgrade steps, including backup and restore and listener migration, then you can restart DBUA.
If post-upgrade steps fail due to encountering an error, then DBUA displays the manual steps for you to finish the upgrade. If the post-upgrade steps stop, then you can defer the saved post upgrade steps to finish the upgrade manually. Post-upgrade steps include moving data, post migration processing, upgrading the time zone file, or configuring Oracle Enterprise Manager.
The option to use Oracle RMAN to restore your database in case the upgrade fails has been improved in this release. In certain cases, DBUA now enables you to restore your database from your own backup.
With RMAN backup, DBUA supports backing up of databases that use Oracle Automatic Storage Management (Oracle ASM).
DBUA generates HTML reports before and after the upgrade. These reports include component status, and also provide the ability to drill down to database objects, including invalid objects where an action to fix a problem might be available.
Upgrading Oracle Grid Infrastructure for Oracle Database 12c includes root script automation procedures, improved ability to perform full release and patch upgrades, and enhancements to status checks and upgrade checkpoints to provide improved stability and ease of use.
See Also:Oracle Grid Infrastructure Installation Guide for your operating system for information about upgrading Oracle Grid Infrastructure
The pluggable database (PDB) feature is new in Oracle Database 12c. Oracle Database uses multitenant architecture and you can configure a multitenant container database (CDB) and have one PDB. If you purchase the Oracle Multitenant option, then you can have multiple PDBs inside a CDB. One of the key benefits of the multitenant architecture is that you can upgrade or apply a patch to a CDB and the upgrade or patch is implemented on all the PDBs within that CDB. This greatly simplifies administration for upgrading.
See Also:Oracle Database Concepts for an overview and documentation roadmap for working with PDBs
Oracle XML Database (Oracle XML DB) is now a mandatory component of Oracle Database. You cannot uninstall it, and there is no option not to include it when you create a new database. If during the upgrade, Oracle XML DB is not found, then Oracle XML DB is automatically loaded into the SYSAUX tablespace. The upgraded Oracle Database includes Oracle XML DB.
See Also:Oracle XML DB Developer's Guide for information about new features in Oracle XML DB
In addition to deprecating one or more features that directly affect the upgrade process, this release includes deprecations for a range of Oracle Database features and respective replacements for those features.
catupgrd.sql upgrade script is deprecated in Oracle Database 12c. The Parallel Upgrade Utility,
catupgrd.sql. See "Deprecation of catupgrd.sql Script and Introduction of New catctl.pl Utility" for more details.
Changes and deprecations that affect the behavior of Oracle Database after upgrading to the new Oracle Database 12c release are described in Chapter 8, "Deprecated and Desupported Features for Oracle Database 12c."
Changes and deprecations that affect the behavior of earlier releases are described in Appendix A, "Changes for Earlier Releases of Oracle Database."
The comprehensive list of features that are desupported in Oracle Database 12c is provided in Chapter 8, "Deprecated and Desupported Features for Oracle Database 12c." Oracle recommends that you check the entire chapter for changes that affect your database environment.