# Upgrading the RDS for Oracle DB engine
When Amazon RDS supports a new version of Oracle Database, you can upgrade your DB instances to the new version. For information about which Oracle versions are available on Amazon RDS, see [https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/Welcome.html](https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/Welcome.html).
**Important**
RDS for Oracle Databases 11g, 12c, and 18c are no longer supported. If you maintain Oracle Database 11g, 12c, or 18c snapshots, you can upgrade them to a later release. For more information, see [Upgrading an Oracle DB snapshot](USER_UpgradeDBSnapshot.Oracle.md).
**Topics**
+ [
# Overview of RDS for Oracle engine upgrades
](USER_UpgradeDBInstance.Oracle.Overview.md)
+ [
# Oracle major version upgrades
](USER_UpgradeDBInstance.Oracle.Major.md)
+ [
# Oracle minor version upgrades
](USER_UpgradeDBInstance.Oracle.Minor.md)
+ [
# Considerations for Oracle database upgrades
](USER_UpgradeDBInstance.Oracle.OGPG.md)
+ [
# Testing an Oracle DB upgrade
](USER_UpgradeDBInstance.Oracle.UpgradeTesting.md)
+ [
# Upgrading the version of an RDS for Oracle DB instance
](USER_UpgradeDBInstance.Oracle.Upgrading.md)
+ [
# Upgrading an Oracle DB snapshot
](USER_UpgradeDBSnapshot.Oracle.md)
# Overview of RDS for Oracle engine upgrades
Before upgrading your RDS for Oracle DB instance, familiarize yourself with the following concepts.
**Topics**
+ [
## Major and minor version upgrades
](#USER_UpgradeDBInstance.Oracle.Overview.versions)
+ [
## Support dates and mandatory upgrades for RDS for Oracle
](#Aurora.VersionPolicy.MajorVersionLifetime)
+ [
## Oracle engine version management
](#Oracle.Concepts.Patching)
+ [
## Automatic snapshots during engine upgrades
](#USER_UpgradeDBInstance.Oracle.Overview.snapshots)
+ [
## Oracle upgrades in a Multi-AZ deployment
](#USER_UpgradeDBInstance.Oracle.Overview.multi-az)
+ [
## Oracle upgrades of read replicas
](#USER_UpgradeDBInstance.Oracle.Overview.read-replicas)
## Major and minor version upgrades
Major versions are major releases of Oracle Database that occur every 1-2 years. Oracle Database 19c and Oracle Database 21c are major releases.
Every quarter, RDS for Oracle releases new minor engine versions for every supported major engine. A Release Update (RU) engine version incorporates bug fixes from Oracle by including the RU patches for the specified quarter. For example, 21.0.0.0.ru-2024-10.rur-2024-10.r1 is a minor version of Oracle Database 21c that incorporates the October 2024 RU.
A Spatial Patch Bundle (SPB) engine version contains RU patches and patches specific to Oracle Spatial. 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. Typically, RDS for Oracle releases SPBs 2–3 weeks after the corresponding RU. For an explanation of the differences between RUs and SPBs, see [Release Updates (RUs) and Spatial Patch Bundles (SPBs)](USER_UpgradeDBInstance.Oracle.Minor.md#RUs-and-SPBs). For information about supported RUs and SPBs, see [Release notes for Amazon Relational Database Service (Amazon RDS) for Oracle](https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes).
RDS for Oracle supports the following upgrades to a DB instance.
| Upgrade type | Application compatibility | Upgrade methods | Sample upgrade path |
| --- | --- | --- | --- |
| Major version | A major version upgrade can introduce changes that aren't compatible with existing applications. | Manual only | From Oracle Database 19c to Oracle Database 21c |
| Minor version | A minor version upgrade includes only changes that are backward-compatible with existing applications. | Automatic or manual | From 21.0.0.0.ru-2023-07.rur-2022-07.r1 to 21.0.0.0.ru-2023-10.rur-2022-10.r1 |
**Important**
When you upgrade your DB engine, an outage occurs. The duration of the outage depends on your engine version and DB instance size.
Make sure that you thoroughly test any upgrade to verify that your applications work correctly before applying the upgrade to your production databases. For more information, see [Testing an Oracle DB upgrade](USER_UpgradeDBInstance.Oracle.UpgradeTesting.md).
## Support dates and mandatory upgrades for RDS for Oracle
Database versions of RDS for Oracle have expected support dates. When a major or minor version of an RDS for Oracle DB engine nears its end-of-support date, RDS begins mandatory upgrades, also known as *forced upgrades*. RDS publishes the following information:
+ A recommendation for you to begin manually upgrading instances on deprecated versions to supported versions
+ A date after which you can no longer create instances on the unsupported versions
+ A date on which RDS begins to upgrade your instances to supported versions automatically during maintenance windows
+ A date on which RDS begins to upgrade your instances to supported versions automatically outside of maintenance windows
**Important**
Forced upgrades can have unexpected consequences for CloudFormation stacks. If you rely on RDS to upgrade your DB instances automatically, you might encounter issues with CloudFormation.
This section contains the following topics:
**Topics**
+ [
### Support dates for major releases of RDS for Oracle
](#oracle-major-support-dates)
+ [
### Support dates for minor versions of RDS for Oracle
](#oracle-minor-support-dates)
### Support dates for major releases of RDS for Oracle
RDS for Oracle major versions remain available at least until the end of support date for the corresponding Oracle Database release version. You can use the following dates to plan your testing and upgrade cycles. These dates represent the earliest date that an upgrade to a newer version might be required. If Amazon extends support for an RDS for Oracle version for longer than originally stated, we plan to update this table to reflect the later date.
**Note**
You can view the major versions of your Oracle databases by running the [describe-db-major-engine-versions](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-db-major-engine-versions.html) AWS CLI command or by using the [DescribeDBMajorEngineVersions](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_DescribeDBMajorEngineVersions.html) RDS API operation.
| Oracle Database major release version | Expected date for upgrading to a newer version |
| --- | --- |
| Oracle Database 19c | December 31, 2029 with BYOL Premier Support (fees waived for Extended Support) December 31, 2032 with BYOL Extended Support (extra cost) or an Unlimited License Agreement December 31, 2029 with License Included (LI) |
| Oracle Database 21c | July 31, 2027 (not available for Extended Support) |
RDS notifies you at least 12 months before you need to upgrade to a newer major version. The notification describes the upgrade process, including the timing of important milestones, the effect on your DB instances, and recommended actions. We recommend that you thoroughly test your applications with new RDS for Oracle versions before you upgrade your database to a major version.
After this advance notification period, an automatic upgrade to the subsequent major version might be applied to any RDS for Oracle DB instance still running the older version. If so, the upgrade is started during scheduled maintenance windows.
For more information, see [ Release Schedule of Current Database Releases](https://support.oracle.com/knowledge/Oracle%20Database%20Products/742060_1.html) in My Oracle Support.
### Support dates for minor versions of RDS for Oracle
In some cases, we end support for minor versions of major releases in RDS for Oracle. RDS notifies you at least 6 months before you need to upgrade to a newer minor version. The notification describes the upgrade process, including the timing of important milestones, the effect on the DB instances running the deprecated minor version, and recommended actions. We recommend that you thoroughly test your applications with new RDS for Oracle versions before you upgrade your database to a new minor version.
For more information about deprecated and desupported minor versions, see [Release notes for Amazon Relational Database Service (Amazon RDS) for Oracle](https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/Welcome.html).
## Oracle engine version management
With DB engine version management, you control when and how the database engine is patched and upgraded. You get the flexibility to maintain compatibility with database engine patch versions. You can also test new patch versions of RDS for Oracle to ensure they work with your application before deploying them in production. In addition, you upgrade the versions on your own terms and timelines.
**Note**
Amazon RDS periodically aggregates official Oracle database patches using an Amazon RDS-specific DB engine version. To see a list of which Oracle patches are contained in an Amazon RDS Oracle-specific engine version, go to [https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/Welcome.html](https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/Welcome.html).
## Automatic snapshots during engine upgrades
During upgrades of an Oracle DB instance, snapshots offer protection against upgrade issues. If the backup retention period for your DB instance is greater than 0, Amazon RDS takes the following DB snapshots during the upgrade:
1. A snapshot of the DB instance before any upgrade changes have been made. If the upgrade fails, you can restore this snapshot to create a DB instance running the old version.
1. A snapshot of the DB instance after the upgrade completes.
**Note**
To change your backup retention period, see [Modifying an Amazon RDS DB instance](Overview.DBInstance.Modifying.md).
After an upgrade, you can't revert to the previous engine version. However, you can create a new Oracle DB instance by restoring the pre-upgrade snapshot.
## Oracle upgrades in a Multi-AZ deployment
If your DB instance is in a Multi-AZ deployment, Amazon RDS upgrades both the primary and standby replicas. If no operating system updates are required, the primary and standby upgrades occur simultaneously. The instances are not available until the upgrade completes.
If operating system updates are required in a Multi-AZ deployment, Amazon RDS applies the updates when you request the database upgrade. Amazon RDS performs the following steps:
1. Updates the operating system on the current standby DB instance.
1. Fails over the primary DB instance to the standby DB instance.
1. Upgrades the database version on the new primary DB instance, which was formerly the standby instance. The primary database is unavailable during the upgrade.
1. Updates the operating system on the new standby DB instance, which was formerly the primary DB instance.
1. Upgrades the database version on the new standby DB instance.
1. Fails over the new primary DB instance back to the original primary DB instance, and the new standby DB instance back to the original standby DB instance. Thus, Amazon RDS returns the replication configuration to its original state.
## Oracle upgrades of read replicas
The Oracle DB engine version of the source DB instance and all of its read replicas must be the same. Amazon RDS performs the upgrade in the following stages:
1. Upgrades the source DB instance. The read replicas are available during this stage.
1. Upgrades the read replicas in parallel, regardless of the replica maintenance windows. The source DB is available during this stage.
For major version upgrades of cross-Region read replicas, Amazon RDS performs additional actions:
+ Generates an option group for the target version automatically
+ Copies all options and option settings from the original option group to the new option group
+ Associates the upgraded cross-Region read replica with the new option group
# Oracle major version upgrades
To perform a major version upgrade, modify the DB instance manually. Major version upgrades don't occur automatically.
**Important**
Make sure that you thoroughly test any upgrade to verify that your applications work correctly before applying the upgrade to your production databases. For more information, see [Testing an Oracle DB upgrade](USER_UpgradeDBInstance.Oracle.UpgradeTesting.md).
**Topics**
+ [
## Supported versions for major upgrades
](#USER_UpgradeDBInstance.Oracle.Major.supported-versions)
+ [
## Supported instance classes for major upgrades
](#USER_UpgradeDBInstance.Oracle.Major.instance-classes)
+ [
## Gathering statistics before major upgrades
](#USER_UpgradeDBInstance.Oracle.Major.gathering-stats)
+ [
## Allowing major upgrades
](#USER_UpgradeDBInstance.Oracle.Major.allowing-upgrades)
## Supported versions for major upgrades
Amazon RDS supports the following major version upgrades.
****
| Current version | Upgrade supported |
| --- | --- |
| 19.0.0.0 using the CDB architecture | 21.0.0.0 |
A major version upgrade of Oracle Database must upgrade to a Release Update (RU) that was released in the same month or later. Major version downgrades aren't supported for any Oracle Database versions.
## Supported instance classes for major upgrades
Your current Oracle DB instance might run on a DB instance class that isn't supported for the version to which you are upgrading. In this case, before you upgrade, migrate the DB instance to a supported DB instance class. For more information about the supported DB instance classes for each version and edition of Amazon RDS for Oracle, see [DB instance classes](Concepts.DBInstanceClass.md).
## Gathering statistics before major upgrades
Before you perform a major version upgrade, Oracle recommends that you gather optimizer statistics on the DB instance that you are upgrading. This action can reduce DB instance downtime during the upgrade.
To gather optimizer statistics, connect to the DB instance as the master user, and run the `DBMS_STATS.GATHER_DICTIONARY_STATS` procedure, as in the following example.
```
EXEC DBMS_STATS.GATHER_DICTIONARY_STATS;
```
For more information, see [ GATHER\$1DICTIONARY\$1STATS Procedure](https://docs.oracle.com/en/database/oracle/oracle-database/19/arpls/DBMS_STATS.html?source=%3Aso%3Atw%3Aor%3Aawr%3Aodv%3A%3A#GUID-867989C7-ADFC-4464-8981-437CEA7F331E) in the Oracle documentation.
## Allowing major upgrades
A major engine version upgrade might be incompatible with your application. The upgrade is irreversible. If you specify a major version for the EngineVersion parameter that is different from the current major version, you must allow major version upgrades.
If you upgrade a major version using the CLI command [modify-db-instance](https://docs.aws.amazon.com/cli/latest/reference/rds/modify-db-instance.html), specify `--allow-major-version-upgrade`. This setting isn't persistent, so you must specify `--allow-major-version-upgrade` whenever you perform a major upgrade. This parameter has no impact on upgrades of minor engine versions. For more information, see [Upgrading a DB instance engine version](USER_UpgradeDBInstance.Upgrading.md).
If you upgrade a major version using the console, you don't need to choose an option to allow the upgrade. Instead, the console displays a warning that major upgrades are irreversible.
# Oracle minor version upgrades
In RDS for Oracle, a minor version upgrade is an update to a major DB engine version. In RDS, a minor engine version is either a Release Update (RU) or Spatial Patch Bundle (SPB). For example, if your DB instance runs major version Oracle Database 19c and minor version 19.0.0.0.ru-2025-10.rur-2025-10.r1, you can upgrade your DB engine to minor version 19.0.0.0.ru-2026-01.rur-2026-01.r1. RDS for Oracle doesn't support minor version downgrades.
You can upgrade your DB engine to a minor version manually or automatically. To learn how to upgrade manually, see [Manually upgrading the engine version](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.Manual). To learn how to configure automatic upgrades, see [Automatically upgrading the minor engine version](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.AutoMinorVersionUpgrades). Whether you upgrade manually or automatically, a minor version upgrade entails downtime. Consider this downtime when you plan your upgrades.
Amazon RDS also supports upgrade rollout policy to manage automatic minor version upgrades across multiple database resources and AWS accounts. For more information, see [Using AWS Organizations upgrade rollout policy for automatic minor version upgrades](RDS.Maintenance.AMVU.UpgradeRollout.md).
**Important**
Make sure that you thoroughly test any upgrade to verify that your applications work correctly before applying the upgrade to your production databases. For more information, see [Testing an Oracle DB upgrade](USER_UpgradeDBInstance.Oracle.UpgradeTesting.md).
**Topics**
+ [
## Release Updates (RUs) and Spatial Patch Bundles (SPBs)
](#RUs-and-SPBs)
+ [
## Turning on automatic minor version upgrades for Oracle
](#oracle-minor-version-upgrade-tuning-on)
+ [
## Using AWS Organizations upgrade rollout policy for automatic minor version upgrades
](#oracle-minor-version-upgrade-rollout)
+ [
## Notification of automatic minor version upgrades in RDS for Oracle
](#oracle-minor-version-upgrade-advance)
+ [
## How Amazon RDS schedules automatic minor version upgrades
](#oracle-minor-version-upgrade-scheduled)
+ [
## Managing an automatic minor version upgrade in RDS for Oracle
](#oracle-minor-version-upgrade-managing)
## Release Updates (RUs) and Spatial Patch Bundles (SPBs)
In RDS, a release update (RU) is a quarterly minor engine version that includes security fixes, bug fixes, and new features for Oracle Database. A Spatial Patch Bundle (SPB) is an RU engine version that includes patches designed for the Oracle Spatial option. For example, the SPB named 19.0.0.0.ru-2025-01.spb-1.r1 includes all patches in the corresponding RU 19.0.0.0.ru-2025-01.rur-2025-01.r1 plus patches specific to Spatial. SPBs are supported only for Oracle Database 19c.
When your instance is configured for automatic minor version upgrades, RUs and SPBs are on separate upgrade paths. Typically, an SPB is released 2–3 weeks after its corresponding RU. The following table shows sample minor versions for Oracle Database 19c.
| Standard RU upgrade path | SPB upgrade path |
| --- | --- |
| 19.0.0.0.ru-2025-01.rur-2025-01.r1 | 19.0.0.0.ru-2025-01.spb-1.r1 |
| 19.0.0.0.ru-2025-04.rur-2025-04.r1 | 19.0.0.0.ru-2025-04.spb-1.r1 |
| 19.0.0.0.ru-2025-07.rur-2025-07.r1 | 19.0.0.0.ru-2025-07.spb-1.r1 |
| 19.0.0.0.ru-2025-10.rur-2025-10.r1 | 19.0.0.0.ru-2025-10.spb-1.r1 |
If your DB instance is configured for automatic upgrades, your instance is on the upgrade path corresponding to your current version. For example, if your DB instance runs version 19.0.0.0.ru-2025-01.rur-2025-01.r1, then when 19.0.0.0.ru-2025-04.rur-2025-04.r1 is released, your instance automatically upgrades to this RU. Similarly, if your DB instance runs 19.0.0.0.ru-2025-01.spb-1.r1, then when 19.0.0.0.ru-2025-04.spb-1.r1 is released, your instance automatically upgrades to this SPB. An instance running 19.0.0.0.ru-2025-01.rur-2025-01.r1, which is an RU, won't automatically upgrade to 19.0.0.0.ru-2025-04.spb-1.r1, which is an SPB on a separate upgrade path.
You can upgrade your DB instance to SPBs even if your instance doesn't use Spatial, but the Spatial patches apply only to Oracle Spatial. You can upgrade manually from an RU to an SPB at the same engine version or higher. For example, you can upgrade your instance from 19.0.0.0.ru-2025-01.rur-2025-01.r1 to either of the following engine versions:
+ 19.0.0.0.ru-2025-01.spb-1.r1
+ 19.0.0.0.ru-2025-04.spb-1.r1
You can upgrade your instance from an SPB to an RU only if the RU is a higher engine version. For example, you can upgrade from SPB version 19.0.0.0.ru-2025-04.spb-1.r1 to a higher RU version 19.0.0.0.ru-2025-07.rur-2025-07.r1 but not to the same RU version 19.0.0.0.ru-2025-04.rur-2025-04.r1.
If your DB instance is configured for automatic minor version upgrades, and you manually upgrade from an RU to an SPB or from an SPB to an RU, your automatic upgrade path changes. Suppose that you manually upgrade from RU version 19.0.0.0.ru-2025-01.rur-2025-01.r1 to SPB version 19.0.0.0.ru-2025-01.spb-1.r1. Your next automatic minor version upgrade will be to SPB version 19.0.0.0.ru-2025-04.spb-1.r1.
Because SPBs function as RUs, the RDS APIs for upgrading your instance to RUs and SPBs are identical. The following commands demonstrate upgrading to an RU and to an SPB.
```
aws rds modify-db-instance \
--db-instance-identifier mydbinstance \
--engine-version 19.0.0.0.ru-2025-01.rur-2025-01.r1
aws rds modify-db-instance \
--db-instance-identifier mydbinstance \
--engine-version 19.0.0.0.ru-2025-01.spb-1.r1
```
For more information about the Oracle Spatial option, see [How Spatial Patch Bundles (SPBs) work](Oracle.Options.Spatial.md#Oracle.Options.Spatial.SPBs). For supported RUs and SPBs for Oracle Database 19c, see [Amazon RDS for Oracle Database 19c (19.0.0.0)](https://docs.aws.amazon.com/AmazonRDS/latest/OracleReleaseNotes/oracle-version-19-0.html).
## Turning on automatic minor version upgrades for Oracle
In an automatic minor version upgrade, RDS applies the latest available minor version to your Oracle database without manual intervention. An Amazon RDS for Oracle DB instance schedules your upgrade during the next maintenance window in the following circumstances:
+ Your DB instance has the **Auto minor version upgrade** option turned on.
+ Your DB instance isn't already running the latest minor DB engine version.
To learn how to turn on automatic upgrades, see [Automatically upgrading the minor engine version](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.AutoMinorVersionUpgrades).
## Using AWS Organizations upgrade rollout policy for automatic minor version upgrades
Amazon RDS for Oracle supports AWS Organizations upgrade rollout policy to manage automatic minor version upgrades across multiple database resources and AWS accounts. This policy eliminates the operational overhead of coordinating automatic minor version upgrades either manually or through custom tools, while ensuring upgrades are first applied in non-production environments before being rolled out to production. When a new minor engine version becomes available, Amazon RDS upgrades your DB instances based on their configured upgrade rollout order:
| Upgrade Rollout Order | Typical Use Case | When Upgrade Begins |
| --- | --- | --- |
| First | Development and Test Environments | Earliest - ideal for validating new versions |
| Second | Staging and Non-critical Production Environments | After "First" phase completes |
| Last | Critical Production Environments | After "Second" phase completes |
**Important**
If you do not configure an upgrade rollout order for your DB instance, it defaults to second.
For detailed information about phase timing and duration, see [How Amazon RDS schedules automatic minor version upgrades](#oracle-minor-version-upgrade-scheduled). For information about configuring upgrade rollout policies in AWS Organizations, see [Using AWS Organizations upgrade rollout policy for automatic minor version upgrades](RDS.Maintenance.AMVU.UpgradeRollout.md).
## Notification of automatic minor version upgrades in RDS for Oracle
If automatic minor version upgrade is enabled on your DB instance, RDS for Oracle creates pending maintenance actions to notify you before applying upgrades. You can view these pending maintenance actions on the **Maintenance & backups** tab of your database details page in the Amazon RDS console.
When a new minor version becomes available, RDS for Oracle publishes an early notification (pending maintenance action). The early notification has the following format:
```
An automatic minor version upgrade to engine-version will be applied during your maintenance window on apply-date based on the upgrade rollout order rollout-order. You can change the upgrade rollout order or apply this upgrade manually at any time before the scheduled date through the AWS console or AWS CLI.
```
`apply-date` in the early notification is the date when Amazon RDS will upgrade your DB instance. `rollout-order` is your upgrade rollout order (first, second, or last). If you have not configured an upgrade rollout policy, this value is second by default. For more information, see [Using AWS Organizations upgrade rollout policy for automatic minor version upgrades](RDS.Maintenance.AMVU.UpgradeRollout.md).
When the upgrade rollout phase begins, the pending maintenance action message changes to the following format:
```
Automatic minor version upgrade to engine-version
```
This message indicates that the upgrade has been scheduled and will be applied during your maintenance window on the scheduled apply date. You can check the scheduled apply date on the **Maintenance & backups** tab of your database details page in the Amazon RDS console or in the `CurrentApplyDate` field of the `describe-pending-maintenance-actions` API response.
The following example shows you can get the details about pending maintenance actions by using the `describe-pending-maintenance-actions` command in the AWS CLI:
```
aws rds describe-pending-maintenance-actions
"PendingMaintenanceActions": [
{
"ResourceIdentifier": "arn:aws:rds:us-east-1:123456789012:db:orclinst1",
"PendingMaintenanceActionDetails": [
{
"Action": "db-upgrade",
"Description": "Automatic minor version upgrade to 21.0.0.0.ru-2024-07.rur-2024-07.r1",
"CurrentApplyDate": "2024-12-02T08:10:00Z"
}
]
}, ...
```
For more information about [describe-pending-maintenance-actions](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-pending-maintenance-actions.html), see the *AWS CLI Command Reference*.
## How Amazon RDS schedules automatic minor version upgrades
When you use AWS Organizations upgrade rollout policy, Amazon RDS upgrades DB instances in phases based on their configured rollout order. This section describes the timing and duration of each phase.
**Phase 0: Early Notification**
When RDS for Oracle releases a new minor version (typically 3 to 4 weeks after Oracle's quarterly RU release), all DB instances with auto minor version upgrade enabled receive an early notification. This notification appears on the **Maintenance & backups** tab of the database details page in the Amazon RDS console and in the `describe-pending-maintenance-actions` API response. The early notification phase lasts 2 weeks. During this phase, no automatic upgrades occur.
**Phase 1: Upgrade Rollout Order First**
At the end of the early notification phase, RDS for Oracle begins upgrading DB instances with the upgrade rollout order first. This phase lasts 2 to 3 weeks for the January, April, July quarterly minor versions, and 7 to 8 weeks for the October quarterly minor version. The extended period for the October minor version provides sufficient time to test the new minor version during the year-end holiday season. New DB instances created during this phase with the upgrade rollout order first will be upgraded automatically.
**Phase 2: Upgrade Rollout Order Second**
At the end of phase 1, RDS for Oracle begins upgrading DB instances with upgrade rollout order second. This phase lasts 2 weeks for all quarterly minor versions. New DB instances created with upgrade rollout order first or second during this phase will be upgraded automatically.
**Phase 3: Upgrade Rollout Order Last**
At the end of Phase 2, RDS for Oracle begins upgrading DB instances with upgrade rollout order last. This phase lasts until the next quarterly minor version release. New DB instances created with upgrade rollout order first, second, or last during this phase will be upgraded automatically.
| Phase | When it starts | Duration | Pending maintenance action message |
| --- | --- | --- | --- |
| Phase 0: Early Notification | When RDS for Oracle releases a new minor version | 2 weeks | An automatic minor version upgrade to engine-version will be applied during your maintenance window on apply-date based on the upgrade rollout order rollout-order. You can change the upgrade rollout order or apply this upgrade manually at any time before the scheduled date through the AWS console or AWS CLI. |
| Phase 1: Upgrade Rollout Order First | End of early notification phase | 2 to 4 weeks for January/April/July minor versions, 7 to 9 weeks for October minor version | Automatic minor version upgrade to engine-version |
| Phase 2: Upgrade Rollout Order Second | End of Phase 1 | 2 weeks | Automatic minor version upgrade to engine-version |
| Phase 3: Upgrade Rollout Order Last | End of Phase 2 | Until the next quarterly minor version release | Automatic minor version upgrade to engine-version |
## Managing an automatic minor version upgrade in RDS for Oracle
When auto minor version upgrade is enabled on your DB instance, Amazon RDS automatically upgrades your DB instance to the latest minor version during your maintenance window. However, you can choose to apply the upgrade manually before the scheduled date using the AWS CLI or on the **Maintenance & backups** tab of the database details page.
To upgrade your DB instance immediately instead of waiting for the scheduled maintenance window:
```
aws rds apply-pending-maintenance-action \
--resource-identifier arn:aws:rds:us-east-1:123456789012:db:orclinst1 \
--apply-action db-upgrade \
--opt-in-type immediate
```
To apply the upgrade during your next maintenance window instead of the scheduled apply date:
```
aws rds apply-pending-maintenance-action \
--resource-identifier arn:aws:rds:us-east-1:123456789012:db:orclinst1 \
--apply-action db-upgrade \
--opt-in-type next-maintenance
```
To opt out of an automatic minor version upgrade, modify your DB instance and turn off the automatic minor version upgrade option. This unschedules any pending automatic upgrade.
To learn more about how to turn off automatic minor version upgrade, see [Automatically upgrading the minor engine version](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.AutoMinorVersionUpgrades). If you need assistance with turning off automatic minor version upgrade, please reach out to the AWS Support.
Sometimes a new minor version becomes available before RDS applies a previous minor version. For example, your instance is running on `21.0.0.0.ru-2025-07.rur-2025-07.r1` when `both 21.0.0.0.ru-2025-10.rur-2025-10.r1` and `21.0.0.0.ru-2026-01.rur-2026-01.r1` are available as upgrade targets. In this situation, to avoid unnecessary downtime for your DB instances, RDS schedules the automatic minor version upgrade to the most recent version, skipping the upgrade to the previous version. In this example, RDS upgrades your instance from `21.0.0.0.ru-2025-07.rur-2025-07.r1` directly to `21.0.0.0.ru-2026-01.rur-2026-01.r1`.
# Considerations for Oracle database upgrades
Before you upgrade your Oracle instance, review the following information.
**Topics**
+ [
## Oracle Multitenant considerations
](#USER_UpgradeDBInstance.Oracle.multi)
+ [
## Option group considerations
](#USER_UpgradeDBInstance.Oracle.OGPG.OG)
+ [
## Parameter group considerations
](#USER_UpgradeDBInstance.Oracle.OGPG.PG)
+ [
## Time zone considerations
](#USER_UpgradeDBInstance.Oracle.OGPG.DST)
+ [
## Spatial Patch Bundle (SPB) considerations
](#USER_UpgradeDBInstance.Oracle.SPB)
## 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](Oracle.Concepts.CDBs.md#Oracle.Concepts.single-tenant).
## 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](USER_WorkingWithOptionGroups.md#USER_WorkingWithOptionGroups.Create) or [Copying an option group](USER_WorkingWithOptionGroups.md#USER_WorkingWithOptionGroups.Copy).
If your DB instance uses a custom option group that contains the `APEX` and `APEX-DEV` options, you can sometimes reduce the upgrade time. To do this, upgrade your version of Oracle APEX at the same time as your DB instance. For more information, see [Upgrading the Oracle APEX version](Appendix.Oracle.Options.APEX.UpgradeandRemove.md#Appendix.Oracle.Options.APEX.Upgrade).
## 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](USER_WorkingWithParamGroups.Creating.md) or [Copying a DB parameter group in Amazon RDS](USER_WorkingWithParamGroups.Copying.md).
## 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](Appendix.Oracle.Options.Timezone.md).
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](Appendix.Oracle.Options.Timezone-file-autoupgrade.md).
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](https://docs.oracle.com/en/database/oracle/oracle-database/19/sutil/oracle-data-pump-overview.html#GUID-9B6C92EE-860E-43DD-9728-735B17B9DA89) 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.
# Testing an Oracle DB upgrade
Before you upgrade your DB instance to a major version, thoroughly test your database and all applications that access the database for compatibility with the new version. We recommend that you use the following procedure.
**To test a major version upgrade**
1. Review the Oracle upgrade documentation for the new version of the database engine to see if there are compatibility issues that might affect your database or applications. For more information, see [Database Upgrade Guide](https://docs.oracle.com/database/121/UPGRD/toc.htm) in the Oracle documentation.
1. If your DB instance uses a custom option group, create a new option group compatible with the new version you are upgrading to. For more information, see [Option group considerations](USER_UpgradeDBInstance.Oracle.OGPG.md#USER_UpgradeDBInstance.Oracle.OGPG.OG).
1. If your DB instance uses a custom parameter group, create a new parameter group compatible with the new version you are upgrading to. For more information, see [Parameter group considerations](USER_UpgradeDBInstance.Oracle.OGPG.md#USER_UpgradeDBInstance.Oracle.OGPG.PG).
1. Create a DB snapshot of the DB instance to be upgraded. For more information, see [Creating a DB snapshot for a Single-AZ DB instance for Amazon RDS](USER_CreateSnapshot.md).
1. Restore the DB snapshot to create a new test DB instance. For more information, see [Restoring to a DB instance](USER_RestoreFromSnapshot.md).
1. Modify this new test DB instance to upgrade it to the new version, by using one of the following methods:
+ [Console](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.Manual.Console)
+ [AWS CLI](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.Manual.CLI)
+ [RDS API](USER_UpgradeDBInstance.Upgrading.md#USER_UpgradeDBInstance.Upgrading.Manual.API)
1. Perform testing:
+ Run as many of your quality assurance tests against the upgraded DB instance as needed to ensure that your database and application work correctly with the new version.
+ Implement any new tests needed to evaluate the impact of any compatibility issues that you identified in step 1.
+ Test all stored procedures, functions, and triggers.
+ Direct test versions of your applications to the upgraded DB instance. Verify that the applications work correctly with the new version.
+ Evaluate the storage used by the upgraded instance to determine if the upgrade requires additional storage. You might need to choose a larger instance class to support the new version in production. For more information, see [DB instance classes](Concepts.DBInstanceClass.md).
1. If all tests pass, upgrade your production DB instance. We recommend that you confirm that the DB instance working correctly before allowing write operations to the DB instance.
# Upgrading the version of an RDS for Oracle DB instance
To manually upgrade the DB engine version of an RDS for Oracle DB instance,use the AWS Management Console, the AWS CLI, or the RDS API. For general information about database upgrades in RDS, see [Upgrading the version of an RDS for Oracle DB instance](#USER_UpgradeDBInstance.Oracle.Upgrading). To get valid upgrade targets, use the AWS CLI [ describe-db-engine-versions](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-db-engine-versions.html) command.
## Console
**To upgrade the engine version of an RDS for Oracle DB instance by using the console**
1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/).
1. In the navigation pane, choose **Databases**, and then choose the DB instance that you want to upgrade.
1. Choose **Modify**.
1. For **DB engine version**, choose a higher database version.
1. Choose **Continue** and check the summary of modifications. Make sure that you understand the implications of a database version upgrade. You can't convert an upgraded DB instance back to the previous version. Make sure you have tested both your database and your application with the new version before continuing.
1. Decide when to schedule your DB instance upgrade. To apply the changes immediately, choose **Apply immediately**. Choosing this option can cause an outage in some cases. For more information, see [Using the schedule modifications setting](USER_ModifyInstance.ApplyImmediately.md).
1. On the confirmation page, review your changes. If they are correct, choose **Modify DB instance** to save your changes.
Alternatively, choose **Back** to edit your changes, or choose **Cancel** to cancel your changes.
## AWS CLI
To upgrade the engine version of an RDS for Oracle DB instance, you can use the CLI [modify-db-instance](https://docs.aws.amazon.com/cli/latest/reference/rds/modify-db-instance.html) command. Specify the following parameters:
+ `--db-instance-identifier` – the name of the RDS for Oracle DB instance.
+ `--engine-version` – the version number of the database engine to upgrade to.
For information about valid engine versions, use the AWS CLI [ describe-db-engine-versions](https://docs.aws.amazon.com/cli/latest/reference/rds/describe-db-engine-versions.html) command.
+ `--allow-major-version-upgrade` – to upgrade the DB engine version.
+ `--no-apply-immediately` – to apply changes during the next maintenance window. To apply changes immediately, use `--apply-immediately`.
**Example**
The following example upgrades a CDB instance named `myorainst` from its current version of `19.0.0.0.ru-2024-01.rur-2024-01.r1` to version `21.0.0.0.ru-2024-04.rur-2024-04.r1`.
For Linux, macOS, or Unix:
```
1. aws rds modify-db-instance \
2. --db-instance-identifier myorainst \
3. --engine-version 21.0.0.0.ru-2024-04.rur-2024-04.r1 \
4. --allow-major-version-upgrade \
5. --no-apply-immediately
```
For Windows:
```
1. aws rds modify-db-instance ^
2. --db-instance-identifier myorainst ^
3. --engine-version 21.0.0.0.ru-2024-04.rur-2024-04.r1 ^
4. --allow-major-version-upgrade ^
5. --no-apply-immediately
```
## RDS API
To upgrade an RDS for Oracle DB instance, use the [ ModifyDBInstance](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_ModifyDBInstance.html) action. Specify the following parameters:
+ `DBInstanceIdentifier` – the name of the DB instance, for example *`myorainst`*.
+ `EngineVersion` – the version number of the database engine to upgrade to. For information about valid engine versions, use the [ DescribeDBEngineVersions](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_DescribeDBEngineVersions.html) operation.
+ `AllowMajorVersionUpgrade` – whether to allow a major version upgrade. To do so, set the value to `true`.
+ `ApplyImmediately` – whether to apply changes immediately or during the next maintenance window. To apply changes immediately, set the value to `true`. To apply changes during the next maintenance window, set the value to `false`.
# Upgrading an Oracle DB snapshot
Upgrading your Oracle DB snapshots in Amazon RDS ensures that your database remains secure, compatible, and fully supported. As older Oracle versions reach the end of patch support, you can upgrade any manual DB snapshots tied to these versions to avoid potential vulnerabilities or service limitations. For more information, see [Oracle engine version management](USER_UpgradeDBInstance.Oracle.Overview.md#Oracle.Concepts.Patching).
Amazon RDS supports upgrading snapshots in all AWS Regions.
## Console
**To upgrade an Oracle DB snapshot**
1. Sign in to the AWS Management Console and open the Amazon RDS console at [https://console.aws.amazon.com/rds/](https://console.aws.amazon.com/rds/).
1. In the navigation pane, choose **Snapshots**, and then select the DB snapshot that you want to upgrade.
1. For **Actions**, choose **Upgrade snapshot**. The **Upgrade snapshot** page appears.
1. Choose the **New engine version** to upgrade the snapshot to.
1. (Optional) For **Option group**, choose the option group for the upgraded DB snapshot. The same option group considerations apply when upgrading a DB snapshot as when upgrading a DB instance. For more information, see [Option group considerations](USER_UpgradeDBInstance.Oracle.OGPG.md#USER_UpgradeDBInstance.Oracle.OGPG.OG).
1. Choose **Save changes** to save your changes.
During the upgrade process, all snapshot actions are disabled for this DB snapshot. Also, the DB snapshot status changes from **available** to **upgrading**, and then changes to **active** upon completion. If the DB snapshot can't be upgraded because of snapshot corruption issues, the status changes to **unavailable**. You can't recover the snapshot from this state.
**Note**
If the DB snapshot upgrade fails, the snapshot is rolled back to the original state with the original version.
## AWS CLI
To upgrade an Oracle DB snapshot by using the AWS CLI, call the [modify-db-snapshot](https://docs.aws.amazon.com/cli/latest/reference/rds/modify-db-snapshot.html) command with the following parameters:
+ `--db-snapshot-identifier` – The name of the DB snapshot.
+ `--engine-version` – The version to upgrade the snapshot to.
You might also need to include the following parameter. The same option group considerations apply when upgrading a DB snapshot as when upgrading a DB instance. For more information, see [Option group considerations](USER_UpgradeDBInstance.Oracle.OGPG.md#USER_UpgradeDBInstance.Oracle.OGPG.OG).
+ `--option-group-name` – The option group for the upgraded DB snapshot.
**Example**
The following example upgrades a DB snapshot.
For Linux, macOS, or Unix:
```
aws rds modify-db-snapshot \
--db-snapshot-identifier mydbsnapshot \
--engine-version 19.0.0.0.ru-2020-10.rur-2020-10.r1 \
--option-group-name default:oracle-se2-19
```
For Windows:
```
aws rds modify-db-snapshot ^
--db-snapshot-identifier mydbsnapshot ^
--engine-version 19.0.0.0.ru-2020-10.rur-2020-10.r1 ^
--option-group-name default:oracle-se2-19
```
## RDS API
To upgrade an Oracle DB snapshot by using the Amazon RDS API, call the [ModifyDBSnapshot](https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_ModifyDBSnapshot.html) operation with the following parameters:
+ `DBSnapshotIdentifier` – The name of the DB snapshot.
+ `EngineVersion` – The version to upgrade the snapshot to.
You might also need to include the `OptionGroupName` parameter. The same option group considerations apply when upgrading a DB snapshot as when upgrading a DB instance. For more information, see [Option group considerations](USER_UpgradeDBInstance.Oracle.OGPG.md#USER_UpgradeDBInstance.Oracle.OGPG.OG).