database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-08-24 09:27:52 +03:00
Code Activity

Remove useless entries for aggregate functions from fmgrtab.c.

Browse Source 
Gen_fmgrtab.pl treated aggregate functions the same as other built-in
functions, which is wasteful because there is no real need to have
entries for them in the fmgr_builtins[] table.  Suppressing those
entries saves about 3KB in the compiled table on my machine; which
is not a lot but it's not nothing either, considering that that
table is pretty "hot".  The only outside code change needed is
that ExecInitWindowAgg() can't be allowed to call fmgr_info_cxt()
on a plain aggregate function.  But that saves a few cycles anyway.

Having done that, the aggregate_dummy() function is unreferenced
and might as well be dropped.  Using "aggregate_dummy" as the prosrc
value for an aggregate is now just a documentation convention not
something that matters.  There was some discussion of using NULL
instead to save a few bytes in pg_proc, but we'd have to remove
prosrc's BKI_FORCE_NOT_NULL marking which doesn't seem a great idea.
Anyway, it's possible there's client-side code that expects to
see "aggregate_dummy" there, so I'm loath to change it without a
strong reason.

Discussion: https://postgr.es/m/533989.1604263665@sss.pgh.pa.us
This commit is contained in:
Tom Lane
2020-11-04 11:25:56 -05:00
parent 113d3591b8
commit f21636e5d5
4 changed files with 13 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/backend/executor/nodeAgg.c
View File

@@ -4935,24 +4935,6 @@ AggRegisterCallback(FunctionCallInfo fcinfo,
}
/*
* aggregate_dummy - dummy execution routine for aggregate functions
*
* This function is listed as the implementation (prosrc field) of pg_proc
* entries for aggregate functions. Its only purpose is to throw an error
* if someone mistakenly executes such a function in the normal way.
*
* Perhaps someday we could assign real meaning to the prosrc field of
* an aggregate?
*/
Datum
aggregate_dummy(PG_FUNCTION_ARGS)
{
elog(ERROR, "aggregate function %u called as normal function",
fcinfo->flinfo->fn_oid);
return (Datum) 0; /* keep compiler quiet */
}
/* ----------------------------------------------------------------
* Parallel Query Support
* ----------------------------------------------------------------