Materialized View Log (Mlog$) Index Not Created in its Default Tablespace
Last updated on FEBRUARY 18, 2015
Applies to:Oracle Database - Enterprise Edition - Version 126.96.36.199 and later
Information in this document applies to any platform.
Starting with 188.8.131.52, an index is created automatically on mlog$ as as when mlog$ table is created.
For more details about change in this behavior, take a look at Doc ID 1959657.1.
The index created when a materialized view log is created appears to be created in the user's default tablespace rather than the same tablespace as the MV log table.
Additionally, if the user has no quota on their default tablespace, the index is not created and an error is not reported, leading to possible performance issues.
As you can see here, there is an index automatically created on mlog table.
Index is created (by default) in user's default tablespace rather than in the same tablespace where mv log resides. Ideally it should create index in the same tablespace where mlog$ resides.
Sign In with your My Oracle Support account
Don't have a My Oracle Support account? Click to get started
My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms