Function datumHashTableHash

src/backend/commands/analyzeutils.c:470–481

* Hash function for MCVFreqPair struct pointer. * Input: * keyPtr - pointer to hash key * keysize - not used, hash function must have this signature * Output: * result - hash value as an unsigned integer */

 * 	result - hash value as an unsigned integer
 */
static uint32
datumHashTableHash(const void *keyPtr, Size keysize)
{
	uint32		result;
	MCVFreqPair *mcvFreqPair = *((MCVFreqPair **)keyPtr);
	FmgrInfo   *hashfunc = &mcvFreqPair->typinfo->hashfunc;
	Oid			collid = mcvFreqPair->typinfo->collid;

	result = DatumGetUInt32(FunctionCall1Coll(hashfunc, collid, mcvFreqPair->mcv));

	return result;
}

/**
 * Match function for MCVFreqPair struct pointer.