database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-11-10 17:42:29 +03:00
Code Activity

+ NULLs handling

Browse Source 
Actually required by multi-column indices support.
	We still don't use btree for 'A is (not) null', but
	now btree keep items with NULL attrs using single rule
	for placing/finding items on pages:
	NULLs greater NOT_NULLs and NULL = NULL.
+ Bulkload code (nbtsort.c) support for multi-column indices
	building and NULLs.
+ Fix for btendscan()->pfree(scanopaque) from Chris Dunlop.
This commit is contained in:
Vadim B. Mikheev
1997-03-24 08:48:16 +00:00
parent 427a87911d
commit 14f6b387b1
5 changed files with 434 additions and 109 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
src/backend/access/nbtree/nbtree.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.16 1997/03/18 18:38:35 scrappy Exp $
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.17 1997/03/24 08:48:11 vadim Exp $
*
* NOTES
* This file contains only the public interface routines.
@@ -219,11 +219,21 @@ btbuild(Relation heap,
* artifact of the strategy map architecture chosen in 1986, not
* of the way nulls are handled here.
*/
/*
* New comments: NULLs handling.
* While we can't do NULL comparison, we can follow simple
* rule for ordering items on btree pages - NULLs greater
* NOT_NULLs and NULL = NULL is TRUE. Sure, it's just rule
* for placing/finding items and no more - keytest'll return
* FALSE for a = 5 for items having 'a' isNULL.
* Look at _bt_skeycmp, _bt_compare and _bt_itemcmp for
* how it works. - vadim 03/23/97
if (itup->t_info & INDEX_NULL_MASK) {
pfree(itup);
continue;
}
*/
itup->t_tid = htup->t_ctid;
btitem = _bt_formitem(itup);
@@ -328,8 +338,12 @@ btinsert(Relation rel, Datum *datum, char *nulls, ItemPointer ht_ctid, Relation
itup = index_formtuple(RelationGetTupleDescriptor(rel), datum, nulls);
itup->t_tid = *ht_ctid;
/*
* See comments in btbuild.
if (itup->t_info & INDEX_NULL_MASK)
return ((InsertIndexResult) NULL);
*/
btitem = _bt_formitem(itup);
@@ -423,7 +437,7 @@ btrescan(IndexScanDesc scan, bool fromEnd, ScanKey scankey)
/* reset the scan key */
so->numberOfKeys = scan->numberOfKeys;
so->numberOfFirstKeys = 0;
so->numberOfFirstKeys = 0; /* may be changed by _bt_orderkeys */
so->qual_ok = 1; /* may be changed by _bt_orderkeys */
if (scan->numberOfKeys > 0) {
memmove(scan->keyData,
@@ -433,10 +447,7 @@ btrescan(IndexScanDesc scan, bool fromEnd, ScanKey scankey)
scankey,
so->numberOfKeys * sizeof(ScanKeyData));
/* order the keys in the qualification */
if (so->numberOfKeys > 1)
_bt_orderkeys(scan->relation, so);
else
so->numberOfFirstKeys = 1;
_bt_orderkeys(scan->relation, so);
}
/* finally, be sure that the scan exploits the tree order */
@@ -499,9 +510,10 @@ btendscan(IndexScanDesc scan)
ItemPointerSetInvalid(iptr);
}
pfree (scan->opaque);
if ( so->keyData != (ScanKey) NULL )
pfree (so->keyData);
pfree (so);
_bt_dropscan(scan);
}