Analysis of SYS_LOB* tables

When you are trying to manage your database size, you might see large SYS_LOB* tables on Oracle based systems.

Questions that will be answered in this blog are:

  • How can I find large SYS_LOB tables in my Oracle based SAP system?
  • How can I find the real table for the SYS_LOB?

Finding SYS_LOB table size

In DB02 select all segments larger than 1 GB with name SYS_LOB*:

Output might be like this:

On the tab Lobs you can see the table:

From SYS_LOB name to table

Next to the direct view in DB02 as shown above, OSS note 2142497 – What to do for large lobsegment on Oracle database? describes several ways of determining the translation from the SYS_LOB label to the real table.

You can use ST04 SQL query and fire this query: replace the SYS_LOB number from the one in your own system:

SELECT OWNER, TABLE_NAME, COLUMN_NAME FROM DBA_LOBS
WHERE 'SYS_LOB0007061918C00006$$' IN (SEGMENT_NAME, INDEX_NAME);

Or in ST04, you launch the DBA view for DBA_LOBS:

Result:

In this case table DMC_INDXCL is the source of the SYS_LOB. Knowing this it will easily lead you to OSS note 2704146 – How to delete data in DMC_INDXCL? – SLT for clean up.

Frequent SYS_LOB tables

Frequent SYS_LOB tables and solutions: