Robert Haas <robertmh...@gmail.com> writes: > On Mon, Apr 9, 2012 at 1:30 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> http://archives.postgresql.org/pgsql-general/2012-01/msg00649.php >> The above-linked discussion also brings up a different point, which is >> that extracting the epoch from a timestamptz is an immutable operation, >> but because it's provided in the context of timestamptz_part we can only >> mark it stable. (That is correct because the other cases depend on the >> timezone setting ... but epoch doesn't.) It seems like it might be >> worth providing a single-purpose function equivalent to extract(epoch), >> so that we could mark it immutable. On the other hand, it's not >> entirely apparent why people would need to create indexes on the epoch >> value rather than just indexing the timestamp itself, so I'm a tad less >> excited about this angle of it.
> If somebody needs it I'd probably be in favor of doing it. I'm not > sure I'd do it on spec. Hmm, I thought depesz was asking for such a function here: http://archives.postgresql.org/pgsql-hackers/2012-01/msg01690.php but now that I look more closely, he may have just meant that as an alternative to touching the existing behavior of timestamp_part. But providing a new function wouldn't be enough to solve the problem that timestamp_part's immutability marking is wrong. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
