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Fix some more hashjoin-related bugs in pg_operator. Fix

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hashjoin's hashFunc() so that it does the right thing with pass-by-value
data types (the old code would always return 0 for int2 or char values,
which would work but would slow things down a lot).  Extend opr_sanity
regress test to catch more kinds of errors.
This commit is contained in:
Tom Lane
1999-04-07 23:33:33 +00:00
parent 1819e89a0e
commit af87148065
4 changed files with 125 additions and 100 deletions
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76
src/backend/executor/nodeHash.c
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@ -6,7 +6,7 @@
* Copyright (c) 1994, Regents of the University of California
*
*
* $Id: nodeHash.c,v 1.31 1999/02/13 23:15:22 momjian Exp $
* $Id: nodeHash.c,v 1.32 1999/04/07 23:33:30 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -41,7 +41,7 @@ extern int NBuffers;
static int HashTBSize;
static void mk_hj_temp(char *tempname);
static int hashFunc(char *key, int len);
static int hashFunc(Datum key, int len, bool byVal);
static int ExecHashPartition(Hash *node);
static RelativeAddr hashTableAlloc(int size, HashJoinTable hashtable);
static void ExecHashOverflowInsert(HashJoinTable hashtable,
@ -580,10 +580,8 @@ ExecHashGetBucket(HashJoinTable hashtable,
* compute the hash function
* ------------------
*/
if (execConstByVal)
bucketno = hashFunc((char *) &keyval, execConstLen) % hashtable->totalbuckets;
else
bucketno = hashFunc((char *) keyval, execConstLen) % hashtable->totalbuckets;
bucketno = hashFunc(keyval, execConstLen, execConstByVal) % hashtable->totalbuckets;
#ifdef HJDEBUG
if (bucketno >= hashtable->nbuckets)
printf("hash(%d) = %d SAVED\n", keyval, bucketno);
@ -771,41 +769,45 @@ ExecScanHashBucket(HashJoinState *hjstate,
* ----------------------------------------------------------------
*/
static int
hashFunc(char *key, int len)
hashFunc(Datum key, int len, bool byVal)
{
unsigned int h;
int l;
unsigned char *k;
unsigned int h = 0;
unsigned char *k;
/*
* If this is a variable length type, then 'k' points to a "struct
* varlena" and len == -1. NOTE: VARSIZE returns the "real" data
* length plus the sizeof the "vl_len" attribute of varlena (the
* length information). 'k' points to the beginning of the varlena
* struct, so we have to use "VARDATA" to find the beginning of the
* "real" data.
*/
if (len == -1)
{
l = VARSIZE(key) - VARHDRSZ;
k = (unsigned char *) VARDATA(key);
}
else
{
l = len;
k = (unsigned char *) key;
if (byVal) {
/*
* If it's a by-value data type, use the 'len' least significant bytes
* of the Datum value. This should do the right thing on either
* bigendian or littleendian hardware --- see the Datum access
* macros in c.h.
*/
while (len-- > 0) {
h = (h * PRIME1) ^ (key & 0xFF);
key >>= 8;
}
} else {
/*
* If this is a variable length type, then 'k' points to a "struct
* varlena" and len == -1. NOTE: VARSIZE returns the "real" data
* length plus the sizeof the "vl_len" attribute of varlena (the
* length information). 'k' points to the beginning of the varlena
* struct, so we have to use "VARDATA" to find the beginning of the
* "real" data.
*/
if (len == -1)
{
len = VARSIZE(key) - VARHDRSZ;
k = (unsigned char *) VARDATA(key);
}
else
{
k = (unsigned char *) key;
}
while (len-- > 0)
h = (h * PRIME1) ^ (*k++);
}
h = 0;
/*
* Convert string to integer
*/
while (l--)
h = h * PRIME1 ^ (*k++);
h %= PRIME2;
return h;
return h % PRIME2;
}
/* ----------------------------------------------------------------