Re: hash-join forgets tuples

Tom Lane <tgl@sss.pgh.pa.us> writes:

> Sebastian Freundt <hroptatyr@gna.org> writes:
>> using a highly surjective left (or inner) join to a table reveals data
>> loss if the hash join method is used.
>
> In which PG version?  Given that you appear to be playing with 8.1devel
> code, you might be needing this bug fix:
>
> 2005-07-23 22:25  tgl
>
>     * src/backend/nodes/tidbitmap.c: Fix logic error in tbm_intersect:
>     the intersection of a normal page and a lossy page has to be lossy,
>     because we don't know exactly which tuples on the page should
>     remain part of the bitmap.  Per Jie Zhang.

Ah, good hint. Indeed it is 8.1-devel. Let me examine your proposal.
Thanks Tom!

Regards,
Sebastian