Upgrading a DB instance for Amazon RDS Custom for SQL Server

You can upgrade an Amazon RDS Custom for SQL Server DB instance by modifying it to use a new DB engine version, the same as you do for Amazon RDS.

The same limitations for upgrading an RDS Custom for SQL Server DB instance apply as for modifying an RDS Custom for SQL Server DB instance in general. For more information, see Modifying an RDS Custom for SQL Server DB instance.

For general information about upgrading DB instances, see Upgrading a DB instance engine version.

If you upgrade an RDS Custom for SQL Server DB instance in a Multi-AZ deployment, then Amazon RDS performs rolling upgrades, so you have an outage only for the duration of a failover. For more information, see Multi-AZ and in-memory optimization considerations.

Major version upgrades

Amazon RDS Custom for SQL Server currently supports the following major version upgrades.

You can use an Amazon CLI query, such as the following example, to find the available upgrades for a particular database engine version.

aws rds describe-db-engine-versions \
    --engine custom-sqlserver-se \
    --engine-version 15.00.4322.2.v1 \
    --query "DBEngineVersions[*].ValidUpgradeTarget[*].{EngineVersion:EngineVersion}" \
    --output table

aws rds describe-db-engine-versions ^
    --engine custom-sqlserver-se ^
    --engine-version 15.00.4322.2.v1 ^
    --query "DBEngineVersions[*].ValidUpgradeTarget[*].{EngineVersion:EngineVersion}" ^
    --output table

Database compatibility level

You can use Microsoft SQL Server database compatibility levels to adjust some database behaviors to mimic previous versions of SQL Server. For more information, see Compatibility level in the Microsoft documentation.

When you upgrade your DB instance, all existing databases remain at their original compatibility level. For example, if you upgrade from SQL Server 2019 to SQL Server 2022, all existing databases have a compatibility level of 150. Any new database created after the upgrade have compatibility level 160.

You can change the compatibility level of a database by using the ALTER DATABASE command. For example, to change a database named customeracct to be compatible with SQL Server 2022, issue the following command:

ALTER DATABASE customeracct SET COMPATIBILITY_LEVEL = 160