postgresql/src/backend/access
Robert Haas 81c5e46c49 Introduce 64-bit hash functions with a 64-bit seed.
This will be useful for hash partitioning, which needs a way to seed
the hash functions to avoid problems such as a hash index on a hash
partitioned table clumping all values into a small portion of the
bucket space; it's also useful for anything that wants a 64-bit hash
value rather than a 32-bit hash value.

Just in case somebody wants a 64-bit hash value that is compatible
with the existing 32-bit hash values, make the low 32-bits of the
64-bit hash value match the 32-bit hash value when the seed is 0.

Robert Haas and Amul Sul

Discussion: http://postgr.es/m/CA+Tgmoafx2yoJuhCQQOL5CocEi-w_uG4S2xT0EtgiJnPGcHW3g@mail.gmail.com
2017-08-31 22:21:21 -04:00
..
brin Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n). 2017-08-20 11:19:07 -07:00
common Refactor typcache.c's record typmod hash table. 2017-08-22 16:11:54 -07:00
gin Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n). 2017-08-20 11:19:07 -07:00
gist Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n). 2017-08-20 11:19:07 -07:00
hash Introduce 64-bit hash functions with a 64-bit seed. 2017-08-31 22:21:21 -04:00
heap Separate reinitialization of shared parallel-scan state from ExecReScan. 2017-08-30 13:18:16 -04:00
index Phase 3 of pgindent updates. 2017-06-21 15:35:54 -04:00
nbtree Remove dedicated B-tree root-split record types. 2017-08-16 12:24:40 +03:00
rmgrdesc Remove dedicated B-tree root-split record types. 2017-08-16 12:24:40 +03:00
spgist Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n). 2017-08-20 11:19:07 -07:00
tablesample Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
transam Clean up shm_mq cleanup. 2017-08-31 15:10:24 -04:00
Makefile TABLESAMPLE, SQL Standard and extensible 2015-05-15 14:37:10 -04:00