Horton

Re: Since '2001-09-09 01:46:40'::timestamp microseconds are lost when extracting epoch

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

View thread View on postgr.es
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Thomas Munro <thomas.munro@gmail.com>, Petr Fedorov <petr.fedorov@phystech.edu>
Date: 2020-09-06T23:46:32Z
Lists: pgsql-bugs, pgsql-hackers

Attachments

Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
> Here is a new patch series version.
> I have created a new internal function for converting integers to 
> numeric, to make the implementation a bit more elegant and compact.

I reviewed the 0002 patch, finding one bug (in int8_sum) and a few
more calls of int8_numeric that could be converted.  I think the
attached updated version is committable, and I'd recommend going
ahead with that regardless of the rest of this.  I hadn't realized
how many random calls of int8_numeric and int4_numeric we'd grown,
but there are a lot, so this is nice cleanup.

I continue to think that we can't commit 0003 in this form, because
of the breakage that will ensure in stored views.  As I said upthread,
we should leave the existing SQL-exposed functions alone, invent
new ones that return numeric, and alter the parser to translate
EXTRACT constructs to the new functions.  This approach would also
provide an "out" for anyone who does complain about the performance
cost --- they can just continue to use the old functions.

			regards, tom lane

Commits

  1. Fix inconsistent equalfuncs.c behavior for FuncCall.funcformat.

  2. Doc: fix discussion of how to get real Julian Dates.

  3. Doc: document EXTRACT(JULIAN ...), improve Julian Date explanation.

  4. Change return type of EXTRACT to numeric

  5. Improve our ability to regurgitate SQL-syntax function calls.

  6. Add more tests for EXTRACT of date type

  7. Expose internal function for converting int64 to numeric

  8. Change floating-point output format for improved performance.