Reversion requirements and limitations

If you used the new database server, you must review a list of reversion requirements and limitations, and then complete any prerequisite tasks before you revert. If the reversion restrictions indicate that you must drop objects from the database, you can unload your data and then reload it in the prior database server.

Reversion requirements and limitations are described in the following tables:

Table 1. Requirements and limitations when reverting to any version of the server

Each row in this table lists an item that you cannot revert or that requires action before you can revert to any prior version of the server.

Reversion requirement or limitation
Revert only to the version from which you migrated: If you need to revert, you must revert to the Informix® version that was your source version before you migrated to Version 14.10.
New databases created in the new version of the server: If you created a new database in the new version of the server, you cannot revert the database back to an earlier version of the server. If the data is required, you can unload the data and reload it in the prior version of the server.
New procedures, expression-based fragmented tables, expression-based fragmented indexes, check constraints, and triggers: These cannot be reverted. You must remove any new procedures, fragmented tables, expression-based fragmented indexes, check constraints, and triggers.
Note: Expression-based fragmentation includes fragment by expression, fragment by interval, and fragment by list.
New built-in routines: These cannot be reverted.
New configuration parameters or configuration parameters with new options: These cannot be reverted.
New or outstanding in-place alters: In-place ALTER TABLE statements performed in the new version of the server must not be outstanding against any table.

Ensure that all in-place ALTER operations are complete. If the reversion process does not complete successfully because of in-place ALTER operations, the reversion process lists all the tables that have outstanding in-place alter operations. You must resolve outstanding in-place alter operations on each of the tables in the list before you can revert to the older database server. For more information, see Resolve outstanding in-place alter operations.

Important: Any in-place alter operation that was completed in a version that is before the current version will successfully revert.