pgsql-server/ oc/src/sgml/func.sgml rc/backend ...

Started by Bruce Momjianover 23 years ago1 messagescomitters
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#1Bruce Momjian
bruce@momjian.us

CVSROOT: /cvsroot
Module name: pgsql-server
Changes by: momjian@postgresql.org 03/02/13 00:24:04

Modified files:
doc/src/sgml : func.sgml
src/backend/utils/adt: misc.c
src/include/catalog: catversion.h pg_proc.h
src/include/utils: builtins.h
src/test/regress/expected: random.out
src/test/regress/sql: random.sql

Log message:
The "random" regression test uses a function called oidrand(), which
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