As I suspected, some machines have even more low-order-bit
inaccuracy than the ones I tested. Tweak new test so that
(hopefully) it will pass everywhere. Per buildfarm.
Discussion: https://postgr.es/m/4173840.1673290336@sss.pgh.pa.us
We had some pretty ad-hoc and inefficient code here. To make
matters worse, it didn't test the properties of the random()
function very thoroughly, and it had a test failure rate of
one in every few tens of thousands of runs. Replace the
script altogether with new test cases that prove much more
about random()'s output, run faster, and can be calculated
to have test failure rates on the order of 1e-9.
Having done that, the failure rate of this script should be
negligible in comparison to other causes of test failures,
so remove the "ignore" marker for it in parallel_schedule.
(If it does fail, we'd like to know about that, so "ignore"
was always pretty counterproductive.)
Tom Lane and Dean Rasheed
Discussion: https://postgr.es/m/4173840.1673290336@sss.pgh.pa.us
CREATE TABLE AS has been preferred over SELECT INTO (outside of ecpg
and PL/pgSQL) for a long time. There were still a few uses of SELECT
INTO in tests and documentation, some old, some more recent. This
changes them to CREATE TABLE AS. Some occurrences in the tests remain
where they are specifically testing SELECT INTO parsing or similar.
Discussion: https://www.postgresql.org/message-id/flat/96dc0df3-e13a-a85d-d045-d6e2c85218da%40enterprisedb.com
takes two parameters, an OID x and an integer y, and returns "true" with
probability 1/y (the OID argument is ignored). This can be useful -- for
example, it can be used to select a random sampling of the rows in a
table (which is what the "random" regression test uses it for).
This patch removes that function, because it was old and messy. The old
function had the following problems:
- it was undocumented
- it was poorly named
- it was designed to workaround an optimizer bug that no longer exists
(the OID argument is to ensure that the optimizer won't optimize away
calls to the function; AFAIK marking the function as 'volatile' suffices
nowadays)
- it used a different random-number generation technique than the other
PSRNG-related functions in the backend do (it called random() like they
do, but it had its own logic for setting a set and deciding when to
reseed the RNG).
Ok, this patch removes oidrand(), oidsrand(), and userfntest(), and
improves the SGML docs a little bit (un-commenting the setseed()
documentation).
Neil Conway
