(OO) Support tip: Cannot shrink database space after purging OO database in Oracle 12c
After running purging procedures on OO 10.x with Oracle 12c, one might run a script to shrink the space used.
(Oracle database size reported is the high watermark).
Trying to run the ForceLobShrink procedure ( delivered by OO or normal DBA task of shrinking space) will fail with the following error:
"ORA-10635: Invalid segment or tablespace type" has been detected
On Oracle 12c, the default setup for Lob storage is with "SecureFiles" (as opposed to previous default storage form of "BasicFiles", in Oracle 11g for instance).
If OO tables creation does not specify explicitly this aspect, purging of Securefiles LOBs is not possible.
Thus the stored Purging procedure that Shrinks Lobs space will not work.
An enhancement request was created to find a solution for this known issue:
“QCCR8C32840 Oracle 12c - shrinking space with default Oracle configuration of SecureFiles is not possible”