A technical troubleshooting blog about Oracle with other Databases & Cloud Technologies.

Things to know before Upgrading Oracle 12c DB !!

3 min read
Why there is a need to upgrade Oracle 12c Database?

The most important reason to upgrade 12c is to enjoy continued access to Oracle support. 
Premier Support for Oracle Database 12c has already ended, and Extended Support will expire in July 2022. After this date, Oracle is under no obligation to provide further updates for 12c—even if a massive security vulnerability is discovered afterward.

Extended Support requires paying an additional fee, and rates increase every year that you don’t upgrade to a newer Oracle Database version.

Using an out-of-date version of Oracle Database is highly inadvisable. This is because newer operating systems and hardware likely aren’t certified for use with older versions of Oracle Database.

Finally, upgrading Oracle Database helps you enjoy access to new features and bug fixes to improve database performance, scalability, availability, and security.
What does the upgrade process look like?

The process of upgrading Oracle Database 12c will look slightly different for each customer. Importantly, the actual database upgrade is only one stage in the process.

In general, you can expect to see most or all of the steps below:
Road mapping and planning for the upgrade.

1.Verifying your Oracle environment (e.g. health checks, certifications, software versions, etc.).
2. Verifying your Oracle Grid environment to be at 19c.
3. Verifying your Linux (Oracle, RHEL, etc.) environment to be at min 7.7+ version.
4. Installing Oracle Database 19c into a new Oracle home directory.
5. Creating a container database (CDB) if you select a multitenant architecture.
6. Applying necessary patch for 19C RU.
7. Performing pre-upgrade administrative tasks.
8. Performing upgrade administrative tasks with DBUA ,Autoupgrade utility tool.
9. Performing post-upgrade administrative tasks.
10. Timezone Validation.
Which upgrade method best fits for you?

Oracle database upgrades are complex and technically challenging . The factors influencing your decision here may include:

1. The Oracle database versions that you’re migrating to and from
2. Your choice of operating systems (OS) and hardware
3. The amount of data to migrate
4. Data transformations such as encryption, compression, or changes to the character set
5. The permissible amount of downtime
Most businesses will be able to migrate to Oracle Database 19c using a direct upgrade with the Database Upgrade Assistant (DBUA). Other alternatives include:

1. The dbupgrade command-line utility
2. Transportable tablespaces (i.e. copying tablespaces from one database to another)
3. Importing and exporting data with Oracle Data Pump
Which Oracle Database version should be preferred?

With the Oracle Database 12c support deadline coming up soon, there are three newer versions to which you can upgrade: 18c, 19c, and 21c.

For most businesses, the right answer here will be Oracle Database 19c.

Oracle Database 18c has already left the Oracle support window, even before 12c will. 
Premier Support for 18c ended in June 2021, and Oracle is not offering Extended Support for this version.

Oracle Database 21c is considered an “Innovation Release” of Oracle Database, which offers experimental and cutting-edge new features. Oracle only offers two years of Premier Support, and no Extended Support, for Innovation Releases. This means that Premier Support for 21c will expire in April 2024—the same as the 19c expiration date—but without the possibility to purchase Extended Support.
19c, on the other hand, is a Long-Term Support (LTS) release of Oracle Database. Unlike Innovation Releases, LTS versions offer three years of Extended Support, which means that you can keep using 19c until April 2027.

For most businesses who prefer software stability, and who don’t need the cutting-edge features of 21c, 19c will be the right choice. Upgrading to 19c gives you the flexibility of multiple options as you approach the Premier Support deadline in 2024.