diff options
| author | Robert Haas | 2017-09-01 02:21:21 +0000 |
|---|---|---|
| committer | Robert Haas | 2017-09-01 02:21:21 +0000 |
| commit | 81c5e46c490e2426db243eada186995da5bb0ba7 (patch) | |
| tree | a6cb745131c45a06fa43746a17a69e1dc9daa44a /src/include/fmgr.h | |
| parent | 2d44c58c79aeef2d376be0141057afbb9ec6b5bc (diff) | |
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
Diffstat (limited to 'src/include/fmgr.h')
| -rw-r--r-- | src/include/fmgr.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/include/fmgr.h b/src/include/fmgr.h index 0216965bfc1..b604a5c1624 100644 --- a/src/include/fmgr.h +++ b/src/include/fmgr.h @@ -325,6 +325,7 @@ extern struct varlena *pg_detoast_datum_packed(struct varlena *datum); #define PG_RETURN_FLOAT4(x) return Float4GetDatum(x) #define PG_RETURN_FLOAT8(x) return Float8GetDatum(x) #define PG_RETURN_INT64(x) return Int64GetDatum(x) +#define PG_RETURN_UINT64(x) return UInt64GetDatum(x) /* RETURN macros for other pass-by-ref types will typically look like this: */ #define PG_RETURN_BYTEA_P(x) PG_RETURN_POINTER(x) #define PG_RETURN_TEXT_P(x) PG_RETURN_POINTER(x) |