Considerations for Oracle database upgrades - Amazon Relational Database Service
Oracle Multitenant considerationsOption group considerationsParameter group considerationsTime zone considerationsSPB considerations

Considerations for Oracle database upgrades

Before you upgrade your Oracle instance, review the following information.

Oracle Multitenant considerations

The following table describes the Oracle Database architectures supported in different releases.

Oracle Database release RDS support status Architecture

Oracle Database 21c

 Supported

CDB only

Oracle Database 19c

 Supported

CDB or non-CDB

The following table describes supported and unsupported upgrade paths.

Upgrade path Supported?

CDB to CDB

Yes

Non-CDB to CDB

No, but you can convert a non-CDB to a CDB and then upgrade it

CDB to non-CDB

No

For more information about Oracle Multitenant in RDS for Oracle, see Single-tenant configuration of the CDB architecture.

Option group considerations

If your DB instance uses a custom option group, sometimes Amazon RDS can't automatically assign a new option group. For example, this situation occurs when you upgrade to a new major version. In such cases, specify a new option group when you upgrade. We recommend that you create a new option group, and add the same options to it as in your existing custom option group.

For more information, see Creating an option group or Copying an option group.

If your DB instance uses a custom option group that contains the APEX option, you can sometimes reduce the upgrade time. To do this, upgrade your version of APEX at the same time as your DB instance. For more information, see Upgrading the APEX version.

Parameter group considerations

If your DB instance uses a custom parameter group, sometimes Amazon RDS can't automatically assign your DB instance a new parameter group. For example, this situation occurs when you upgrade to a new major version. In such cases, make sure to specify a new parameter group when you upgrade. We recommend that you create a new parameter group, and configure the parameters as in your existing custom parameter group.

For more information, see Creating a DB parameter group in Amazon RDS or Copying a DB parameter group in Amazon RDS.

Time zone considerations

You can use the time zone option to change the system time zone used by your Oracle DB instance. For example, you might change the time zone of a DB instance to be compatible with an on-premises environment, or a legacy application. The time zone option changes the time zone at the host level. Amazon RDS for Oracle updates the system time zone automatically throughout the year. For more information about the system time zone, see Oracle time zone.

When you create an Oracle DB instance, the database automatically sets the database time zone. The database time zone is also known as the Daylight Saving Time (DST) time zone. The database time zone is distinct from the system time zone.

Between Oracle Database releases, patch sets or individual patches may include new DST versions. These patches reflect the changes in transition rules for various time zone regions. For example, a government might change when DST takes effect. Changes to DST rules may affect existing data of the TIMESTAMP WITH TIME ZONE data type.

If you upgrade an RDS for Oracle DB instance, Amazon RDS doesn't upgrade the database time zone file automatically. To upgrade the time zone file automatically, you can include the TIMEZONE_FILE_AUTOUPGRADE option in the option group associated with your DB instance during or after the engine version upgrade. For more information, see Oracle time zone file autoupgrade.

Alternatively, to upgrade the database time zone file manually, create a new Oracle DB instance that has the desired DST patch. However, we recommend that you upgrade the database time zone file using the TIMEZONE_FILE_AUTOUPGRADE option.

After upgrading the time zone file, migrate the data from your current instance to the new instance. You can migrate data using several techniques, including the following:

  • AWS Database Migration Service

  • Oracle GoldenGate

  • Oracle Data Pump

  • Original Export/Import (desupported for general use)

Note

When you migrate data using Oracle Data Pump, the utility raises the error ORA-39405 when the target time zone version is lower than the source time zone version.

For more information, see TIMESTAMP WITH TIMEZONE restrictions in the Oracle documentation.

Spatial Patch Bundle (SPB) considerations

In RDS for Oracle, release update (RU) is a minor engine version that includes security fixes, bug fixes, and new features for Oracle Database. A Spatial Patch Bundle (SPB) is minor engine version that also includes patches designed for the Oracle Spatial option. For example, 19.0.0.0.ru-2025-01.spb-1.r1 is a minor engine version that contains the RU patches in engine version 19.0.0.0.ru-2025-01.rur-2025-01.r1 plus Spatial patches.

When you upgrade your database to SPBs, consider the following:

  • SPBs are supported only for Oracle Database 19c.

  • Typically, an SPB is released 2–3 weeks after its corresponding quarterly RU.

  • You can upgrade your DB instance to an SPB even if the instance doesn't use the Oracle Spatial option, but the Spatial patches in the engine version apply only to Oracle Spatial. You can create a new instance on an SPB and install the Oracle Spatial option later.

  • If you enable automatic minor version upgrade for your DB instance, your upgrade path depends on whether your instance currently uses an SPB or RU. If your instance uses an SPB, RDS automatically upgrades your instance to the latest SPB. If your instance uses an RU, RDS automatically upgrades your instance to the latest RU.

  • You can manually upgrade your DB instance from an RU to an SPB only if the SPB is the same engine version or higher as your current RU.

  • You can manually upgrade your DB instance from an SPB to an RU only if the RU is a higher version.