Downgrading the metadata for a system fallback

Before falling back from R3.5 to an earlier release, you must use the DOWNGRADE utility to downgrade the metadata to a version that is compatible with the target fallback release. See Version management and interoperability for an overview of the correspondence between metadata versions and SQL/MX releases.

If all metadata already has a compatible version, then DOWNGRADE does not perform any task but simply responds with a message saying that no schemas are affected.

Consider the following scenarios for system fallback:

• If you are using new database features for some objects in v3500 metadata, you must perform the following steps before downgrading the metadata:

  • Use the FEATURE_VERSION_INFO function to obtain the name and object type of database objects that use new features. Such objects prevent a downgrade operation. For more information, see SQL/MX Functions and Expressions in the SQL/MX Reference Manual.

  • Convert each database object that uses new features to a corresponding copy object without new features. For copy objects, you create a copy of the original object without the new features, so as to retain the data.

  • Drop the unsupported objects before executing the DOWNGRADE command.

  • Downgrade to the required version. For more information on how to use the downgrade utility, see SQL/MX Utilities in the SQL/MX Reference Manual.