next gap that is currently blocking redo apply from continuing. After resolving the identified gap and starting redo apply, query the V$ARCHIVE_GAP fixed view again on the physical standby database to determine the next gap sequence, if there is one.
Oracle Database Up-gradation
Why upgrade oracle database to higher version
Oracle release 10g version about a year ago and recently release 11g. Many companies are still using the 8i (8.1.x), 8 (8.0.x) and 7.x database versions. For the most part, everything that is available in a lower version will be available in a higher version as well. To give you an idea of what is "new" consider this...Oracle 8i introduced many new features for the developer. With 8i, you could run Java in the database, you had expanded tools to help with object-oriented development and 8i introduced some enhancements to support larger databases (Materialized Views, additions to partitioning). Oracle 9i introduced many new features to help the DBA such as the ability to change database configuration "on the fly", enhanced availability and enhanced manageability. The advantage of a higher version is that you have more features and better capabilities. You also stay current with the latest "supported" versions. The disadvantage of these new systems is that you have to convert your older databases to the newer versions. This can sometimes cause application changes as well. The advantage of staying at a lower version is that you know it works and you don't have to change a thing. The disadvantage is that you can't use any of the latest and greatest features and that you may lose support
Role of the Database Administrator during the Upgrade
The database administrator (DBA) is the most important person for upgrade process. He involve in each steps, except application testing.
The DBA handle following task for database upgrade:
Analyze current database status and make a plan for upgrade process.
Meeting with everyone involved in the upgrade process and clearly defining their roles Performing test upgrades
Scheduling the test and production upgrades Performing backups of the production database Completing the upgrade of the production database
Performing backups of the newly upgraded Oracle Database production database
Different option for upgrade method, difference and process
We can use three methods to upgrade our oracle database: Export/Import
DBUA
Manually by using Scripts Export/Import
Export/Import utilities only physically copy data from current database to a new database. The current database's Export utility copies specified parts of the database into an export dump file. Then, the Import utility of the new Oracle Database loads the exported data into a new database.
Database Upgrade Assistant
The Database Upgrade Assistant (DBUA) utility configures the database for the new Oracle Database. The Database Upgrade Assistant automates the upgrade process by performing all of the tasks normally performed manually.
The Database Upgrade Assistant performs the following pre-upgrade steps: It checks for any invalid user accounts or roles
It checks for any invalid data types It checks for any disported character sets
It checks for adequate resources, including rollback segments, table spaces, and free disk space
It optionally backs up all necessary files
The Database Upgrade Assistant does not begin the upgrade until it completes all of the pre- upgrade steps.
The Database Upgrade Assistant automatically modifies or creates new required tablespaces, invokes the appropriate upgrade scripts, archives the redo logs, and disables archiving during the upgrade phase.
While the upgrade is running, the Database Upgrade Assistant shows the upgrade progress for each component. The Database Upgrade Assistant writes detailed trace and log files and produces a complete HTML report for later reference. To enhance security, the Database Upgrade Assistant automatically locks new user accounts in the upgraded database. The Database Upgrade Assistant then proceeds to create new configuration files (parameter and listener files) in the new Oracle home.
Manual Upgrade
A manual upgrade consists of running SQL scripts and utilities from a command line to upgrade a database to the new Oracle Database release.
While a manual upgrade gives you finer control over the upgrade process, it is more susceptible to error if any of the upgrade or pre-upgrade steps are either not followed or are performed out of order.
When manually upgrading a database, you must perform the following pre-upgrade steps:
Analyze the database using the Pre-Upgrade Information Tool. The Upgrade Information Tool is a SQL script that ships with the new Oracle Database 10g release, and must be run in the environment of the database being upgraded.
The Upgrade Information Tool displays warnings about possible upgrade issues with the database. It also displays information about required initialization parameters for the new Oracle Database 10g release. Before starting up the new Oracle Database 10g release, make the necessary adjustments to the database.
Add free space to any tablespaces in the database that require additional space, and drop and re-create any redo log files whose size is insufficient for the upgrade.
Adjust the parameter file for the upgrade, removing obsolete initialization parameters and adjusting initialization parameters that might cause upgrade problems.
Depending on the release of the database being upgraded, you may need to perform additional pre-upgrade steps.
After the Upgrade
View the status of the upgrade using the Post-Upgrade Status Tool. The Upgrade Status Tool is a SQL script that ships with the new Oracle Database 10g release, and must be run in the environment of the new Oracle Database 10g release.
Bellow Figure Showing Oracle Database up-gradation Steps
Difference between Up-gradation and Migration
Don‘t think there is no differentiation between Upgrade and migration, basically, if you are simply upgrading software/database to a newer version that‘s called upgrade for example: upgrade 8i database to 9i or 10g. If you have some changes in technology like client/server based to Web based or different platform (moving database from Windows to UNIX based system or via-verse) or different vendor (moving SQL Server database to Oracle) to call it migration.
Oracle Release Numbers
The release number 10.1.0.1.0 is displayed. The significance of each number (reading from left to right) is shown in the following table:
Number Significance
10 Major database release number
1 Database maintenance release number 0 Application server release number 1 Component specific release number 0 Platform specific release number
Upgrade Path
Upgrade path for Oracle database 11g release 1 Direct Upgrade Path
Source Database Target Database 9.2.0.4.0 (or higher) 11.1.x
10.1.0.2.0 (or higher) 11.1.x 10.2.0.1.0 (or higher) 11.1.x Indirect Upgrade Path
Source Database Intermediate Upgrade Path Target Database 7.3.3.0.0 (or lower) 7.3.4.x –> 9.2.0.8 11.1.x
8.0.5.0.0 (or lower) 8.0.6.x –> 9.2.0.8 11.1.x 8.1.7.0.0 (or lower) 8.1.7.4 –> 9.2.0.8 11.1.x 9.0.1.3.0 (or lower) 9.0.1.4 –> 9.2.0.8 11.1.x
Upgrade path for Oracle database 10 releases 2 Direct Upgrade Path
Source Database Target Database 8.1.7.4 (or higher) 10.2.x
9.0.1.4 (or higher) 10.2.x 9.2.0.4 (or higher) 10.2.x 10.1.0.2 (or higher) 10.2.x
Indirect Upgrade Path
Source Database Intermediate Upgrade Path Target Database 7.3.3.0.0 (or lower) 7.3.4 -> 8.1.7.4 10.2.x
7.3.4 8.1.7.4 10.2.x
8.0.n 8.1.7.4 10.2.x