Oracle: Decreasing PCTFREE on large table Question about Oracle Database Enterprise Edition version 19.10.0.0.0 running as a standalone instance.
I have a table with billions of rows. The table has always had PCTFREE set to 10.
It turns out that we only ever perform inserts on this table, no updates, no deletions. I would like to save disk space by lowering PCTFREE to 0.
As I understand it, if I just do ALTER TABLE x PCTFREE 0 then in our case, only future allocated blocks are affected. But all the millions of existing blocks will never be filled above 90% because we never update or delete those rows.
Is there a way to get all the old blocks &quot;re-evaluated&quot; and put back on the freelist after I lower PCTFREE?
I would prefer not to move all of the data (e.g. use CTAS, or expdp+impdp, or delete+insert every row, or dbms_redefinition) because the table is so big that this would take forever and/or use enormous amounts of intermediate space. I just need the database to know that it's now okay to put more rows in the old blocks. Is this possible?
My question was answered on another message board. The answer is to use DBMS_REPAIR.SEGMENT_FIX_STATUS after the change in PCTFREE.
On my platform (sparc64) it's quite buggy, though, with lots of ORA-600 when repairing individual blocks. But repairing all blocks seems to work better for some reason.