Revise hash join and hash aggregation code to use the same datatype-

specific hash functions used by hash indexes, rather than the old
not-datatype-aware ComputeHashFunc routine.  This makes it safe to do
hash joining on several datatypes that previously couldn't use hashing.
The sets of datatypes that are hash indexable and hash joinable are now
exactly the same, whereas before each had some that weren't in the other.

1 files changed, 6 insertions, 7 deletions

diff --git a/src/include/executor/hashjoin.h b/src/include/executor/hashjoin.h
index a2d5f633fc..da7e0bf98c 100644
--- a/src/include/executor/hashjoin.h
+++ b/src/include/executor/hashjoin.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: hashjoin.h,v 1.27 2002/11/30 00:08:20 tgl Exp $
+ * $Id: hashjoin.h,v 1.28 2003/06/22 22:04:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -69,13 +69,12 @@ typedef struct HashTableData
 								 * file */
 
 	/*
-	 * Info about the datatypes being hashed.  We assume that the inner and
-	 * outer sides of each hashclause are the same type, or at least
-	 * binary-compatible types.  Each of these fields points to an array
-	 * of the same length as the number of hash keys.
+	 * Info about the datatype-specific hash functions for the datatypes
+	 * being hashed.  We assume that the inner and outer sides of each
+	 * hashclause are the same type, or at least share the same hash function.
+	 * This is an array of the same length as the number of hash keys.
 	 */
-	int16	   *typLens;
-	bool	   *typByVals;
+	FmgrInfo   *hashfunctions;	/* lookup data for hash functions */
 
 	/*
 	 * During 1st scan of inner relation, we get tuples from executor. If