Migrating to Oracle10g: A Checklist
- Not testing top SQL code and understanding if the CBO in Oracle10g will impact behavior of existing applications. Are there changes in default parameter values (including hidden parameters) that will impact the CBO in Oracle10g?
- Insufficient risk analysis and scenario testing of the migration plan.
- Understanding all of the new features in Oracle10g that are automatically functioning and understanding exactly what they do.
- Migrate lower profile systems first. Understand migration issues on smaller systems before impacting mission critical systems. By the time a mission critical system is migrated to Oracle10g, DBAs should be very comfortable with migration issues and be able to adjust quickly.
Below is a checklist to review before starting the migration process.
- Verify the new release of Oracle works with the version of the operating system Oracle will be installed on. Test all applications thoroughly.
- Review all bugs and fixes identified on the new release. Understand what you're getting into.
- Verify all the software products that will touch the Oracle system work properly. This includes management, scheduling, backup systems, administration scripts, etc. Test backup/recovery procedures thoroughly.
- Look at all the key SQL commands for a system and verify they run acceptable on the new release. The CBO may perform differently on the new release of Oracle. Run SQL traces and understand why key SQL code is running different on the new release.
- There are often new components running in the new release of Oracle, make sure they are clearly understood. Understand if default values change for any initialization parameters (including hidden parameters).
- Run a lot of statistics on the current system and compare how applications run on the new version. Before and after pictures of Oracle, operating system and network are important.
- Check all sources to understand any potential migration issues (Metalink, OTN, Oracle readme files, peers, documentation, Internet). Call Oracle support and vendor support and get detailed documentation on migration issues for specific platform.
- Identify new features that will improve the management, performance, availability and security of the new release. Do not start implementing them until all applications and software are stabilized on the new release.
- Perform detailed review of the migration plan and risk analysis on the migration. Review your critical paths and time frames. Perform scenario testing of different things that could go wrong during the migration. These should be reviewed to test the strength of the migration plan.
- Understand the business benefits of migrating to Oracle10g. What measurements will be used to understand if the migration to Oracle10g has reduced the overall cost of ownership?
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