pgsql: Guard against zero vardata.rel->tuples in estimate_hash_bucketsi - Mailing list pgsql-committers

From Tom Lane
Subject pgsql: Guard against zero vardata.rel->tuples in estimate_hash_bucketsi
Date
Msg-id E1akJ3V-0006bT-O3@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Guard against zero vardata.rel->tuples in estimate_hash_bucketsize().

If the referenced rel was proven empty, we'd compute 0/0 here, which
results in the function returning NaN.  That's a bit more serious
than the other zero-divide case.  Still, it only seems to be possible
in HEAD, so no back-patch.

Per report from Piotr Stefaniak.  I looked through the rest of selfuncs.c
and found no other likely trouble spots.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/d65b665d524a67273b075f468bf3d60ce31f4040

Modified Files
--------------
src/backend/utils/adt/selfuncs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)


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