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

1. BTREE_VERSION_1: using bti_itup->t_tid as unique identifier for a given

Browse Source 
index tuple (logical position within A LEVEL). bti_oid & bti_dummy
taken off from BTItemData.
2. Fix for multi-column indices (nbtsearch.c):
   _bt_binsrch() - for searches on internal pages having keysize <
	number of attrs we point at the last item < the scankey, not at the
	first item = the scankey;
   _bt_moveright() - if keysize < number of attrs we compare scankey with
	_last_ item on current page to decide should we move right or
	not.
This commit is contained in:
Vadim B. Mikheev
1997-04-16 01:48:29 +00:00
parent afd9295786
commit 329fb11262
5 changed files with 170 additions and 102 deletions
Download Patch File Download Diff File Expand all files Collapse all files

41
src/backend/access/nbtree/nbtpage.c
View File

@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.6 1996/11/05 10:35:30 scrappy Exp $
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.7 1997/04/16 01:48:15 vadim Exp $
*
* NOTES
* Postgres btree pages look like ordinary relation pages. The opaque
@@ -38,12 +38,20 @@
#define BTREE_METAPAGE 0
#define BTREE_MAGIC 0x053162
#ifdef BTREE_VERSION_1
#define BTREE_VERSION 1
#else
#define BTREE_VERSION 0
#endif
typedef struct BTMetaPageData {
uint32 btm_magic;
uint32 btm_version;
BlockNumber btm_root;
#ifdef BTREE_VERSION_1
int32 btm_level;
#endif
} BTMetaPageData;
#define BTPageGetMeta(p) \
@@ -95,6 +103,9 @@ _bt_metapinit(Relation rel)
metad.btm_magic = BTREE_MAGIC;
metad.btm_version = BTREE_VERSION;
metad.btm_root = P_NONE;
#ifdef BTREE_VERSION_1
metad.btm_level = 0;
#endif
memmove((char *) BTPageGetMeta(pg), (char *) &metad, sizeof(metad));
op = (BTPageOpaque) PageGetSpecialPointer(pg);
@@ -179,6 +190,17 @@ _bt_getroot(Relation rel, int access)
metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg);
Assert(metaopaque->btpo_flags & BTP_META);
metad = BTPageGetMeta(metapg);
if (metad->btm_magic != BTREE_MAGIC) {
elog(WARN, "Index %s is not a btree",
RelationGetRelationName(rel));
}
if (metad->btm_version != BTREE_VERSION) {
elog(WARN, "Version mismatch on %s: version %d file, version %d code",
RelationGetRelationName(rel),
metad->btm_version, BTREE_VERSION);
}
/* if no root page initialized yet, do it */
if (metad->btm_root == P_NONE) {
@@ -209,6 +231,9 @@ _bt_getroot(Relation rel, int access)
rootblkno = BufferGetBlockNumber(rootbuf);
rootpg = BufferGetPage(rootbuf);
metad->btm_root = rootblkno;
#ifdef BTREE_VERSION_1
metad->btm_level = 1;
#endif
_bt_pageinit(rootpg, BufferGetPageSize(rootbuf));
rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpg);
rootopaque->btpo_flags |= (BTP_LEAF | BTP_ROOT);
@@ -387,7 +412,7 @@ _bt_pageinit(Page page, Size size)
* a reference to or lock on the metapage.
*/
void
_bt_metaproot(Relation rel, BlockNumber rootbknum)
_bt_metaproot(Relation rel, BlockNumber rootbknum, int level)
{
Buffer metabuf;
Page metap;
@@ -400,6 +425,12 @@ _bt_metaproot(Relation rel, BlockNumber rootbknum)
Assert(metaopaque->btpo_flags & BTP_META);
metad = BTPageGetMeta(metap);
metad->btm_root = rootbknum;
#ifdef BTREE_VERSION_1
if ( level == 0 ) /* called from _do_insert */
metad->btm_level += 1;
else
metad->btm_level = level; /* called from btsort */
#endif
_bt_wrtbuf(rel, metabuf);
}
@@ -434,7 +465,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, int access)
item = (BTItem) PageGetItem(page, itemid);
/* if the item is where we left it, we're done */
if (item->bti_oid == stack->bts_btitem->bti_oid)
if ( BTItemSame (item, stack->bts_btitem) )
return (buf);
/* if the item has just moved right on this page, we're done */
@@ -445,7 +476,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, int access)
item = (BTItem) PageGetItem(page, itemid);
/* if the item is where we left it, we're done */
if (item->bti_oid == stack->bts_btitem->bti_oid)
if ( BTItemSame (item, stack->bts_btitem) )
return (buf);
}
}
@@ -471,7 +502,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, int access)
offnum = OffsetNumberNext(offnum)) {
itemid = PageGetItemId(page, offnum);
item = (BTItem) PageGetItem(page, itemid);
if (item->bti_oid == stack->bts_btitem->bti_oid)
if ( BTItemSame (item, stack->bts_btitem) )
return (buf);
}
}