>
> Never, unless you drop and recreate the table. Removing a dropped
> column would change the attnums of following columns, which we
> can't support because the tableoid+attnum is the only persistent
> identifier of a column.
>
> (From memory, operations like VACUUM FULL and CLUSTER will rewrite
> dropped columns with NULLs to reduce their storage impact. But they
> don't go away.)
>
>
Thank you. I remember reading it here that VACUUM FULL does what you describe above.
So even TRUNCATE does not help here?
