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path: root/src/backend/access/nbtree/nbtinsert.c
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Diffstat (limited to 'src/backend/access/nbtree/nbtinsert.c')
-rw-r--r--src/backend/access/nbtree/nbtinsert.c80
1 files changed, 48 insertions, 32 deletions
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 10509cfe8a5..dbd5c9238c5 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -84,7 +84,7 @@ static void _bt_checksplitloc(FindSplitData *state,
int dataitemstoleft, Size firstoldonrightsz);
static bool _bt_pgaddtup(Page page, Size itemsize, IndexTuple itup,
OffsetNumber itup_off);
-static bool _bt_isequal(Relation idxrel, Page page, OffsetNumber offnum,
+static bool _bt_isequal(TupleDesc itupdesc, Page page, OffsetNumber offnum,
int keysz, ScanKey scankey);
static void _bt_vacuum_one_page(Relation rel, Buffer buffer, Relation heapRel);
@@ -343,6 +343,7 @@ _bt_check_unique(Relation rel, IndexTuple itup, Relation heapRel,
IndexUniqueCheck checkUnique, bool *is_unique,
uint32 *speculativeToken)
{
+ TupleDesc itupdesc = RelationGetDescr(rel);
int indnkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
SnapshotData SnapshotDirty;
OffsetNumber maxoff;
@@ -402,7 +403,7 @@ _bt_check_unique(Relation rel, IndexTuple itup, Relation heapRel,
* in real comparison, but only for ordering/finding items on
* pages. - vadim 03/24/97
*/
- if (!_bt_isequal(rel, page, offset, indnkeyatts, itup_scankey))
+ if (!_bt_isequal(itupdesc, page, offset, indnkeyatts, itup_scankey))
break; /* we're past all the equal tuples */
/* okay, we gotta fetch the heap tuple ... */
@@ -566,7 +567,7 @@ _bt_check_unique(Relation rel, IndexTuple itup, Relation heapRel,
/* If scankey == hikey we gotta check the next page too */
if (P_RIGHTMOST(opaque))
break;
- if (!_bt_isequal(rel, page, P_HIKEY,
+ if (!_bt_isequal(itupdesc, page, P_HIKEY,
indnkeyatts, itup_scankey))
break;
/* Advance to next non-dead page --- there must be one */
@@ -849,6 +850,13 @@ _bt_insertonpg(Relation rel,
/* child buffer must be given iff inserting on an internal page */
Assert(P_ISLEAF(lpageop) == !BufferIsValid(cbuf));
+ /* tuple must have appropriate number of attributes */
+ Assert(!P_ISLEAF(lpageop) ||
+ BTreeTupleGetNAtts(itup, rel) ==
+ IndexRelationGetNumberOfAttributes(rel));
+ Assert(P_ISLEAF(lpageop) ||
+ BTreeTupleGetNAtts(itup, rel) ==
+ IndexRelationGetNumberOfKeyAttributes(rel));
/* The caller should've finished any incomplete splits already. */
if (P_INCOMPLETE_SPLIT(lpageop))
@@ -956,6 +964,18 @@ _bt_insertonpg(Relation rel,
}
}
+ /*
+ * Every internal page should have exactly one negative infinity item
+ * at all times. Only _bt_split() and _bt_newroot() should add items
+ * that become negative infinity items through truncation, since
+ * they're the only routines that allocate new internal pages. Do not
+ * allow a retail insertion of a new item at the negative infinity
+ * offset.
+ */
+ if (!P_ISLEAF(lpageop) && newitemoff == P_FIRSTDATAKEY(lpageop))
+ elog(ERROR, "cannot insert second negative infinity item in block %u of index \"%s\"",
+ itup_blkno, RelationGetRelationName(rel));
+
/* Do the update. No ereport(ERROR) until changes are logged */
START_CRIT_SECTION();
@@ -1002,7 +1022,6 @@ _bt_insertonpg(Relation rel,
xl_btree_metadata xlmeta;
uint8 xlinfo;
XLogRecPtr recptr;
- IndexTupleData trunctuple;
xlrec.offnum = itup_off;
@@ -1038,17 +1057,8 @@ _bt_insertonpg(Relation rel,
xlinfo = XLOG_BTREE_INSERT_META;
}
- /* Read comments in _bt_pgaddtup */
XLogRegisterBuffer(0, buf, REGBUF_STANDARD);
- if (!P_ISLEAF(lpageop) && newitemoff == P_FIRSTDATAKEY(lpageop))
- {
- trunctuple = *itup;
- trunctuple.t_info = sizeof(IndexTupleData);
- XLogRegisterBufData(0, (char *) &trunctuple,
- sizeof(IndexTupleData));
- }
- else
- XLogRegisterBufData(0, (char *) itup, IndexTupleSize(itup));
+ XLogRegisterBufData(0, (char *) itup, IndexTupleSize(itup));
recptr = XLogInsert(RM_BTREE_ID, xlinfo);
@@ -1203,6 +1213,7 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
itemid = PageGetItemId(origpage, P_HIKEY);
itemsz = ItemIdGetLength(itemid);
item = (IndexTuple) PageGetItem(origpage, itemid);
+ Assert(BTreeTupleGetNAtts(item, rel) == indnkeyatts);
if (PageAddItem(rightpage, (Item) item, itemsz, rightoff,
false, false) == InvalidOffsetNumber)
{
@@ -1235,20 +1246,25 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
}
/*
- * We must truncate included attributes of the "high key" item, before
- * insert it onto the leaf page. It's the only point in insertion
- * process, where we perform truncation. All other functions work with
- * this high key and do not change it.
+ * Truncate non-key (INCLUDE) attributes of the high key item before
+ * inserting it on the left page. This only needs to happen at the leaf
+ * level, since in general all pivot tuple values originate from leaf
+ * level high keys. This isn't just about avoiding unnecessary work,
+ * though; truncating unneeded key attributes (more aggressive suffix
+ * truncation) can only be performed at the leaf level anyway. This is
+ * because a pivot tuple in a grandparent page must guide a search not
+ * only to the correct parent page, but also to the correct leaf page.
*/
if (indnatts != indnkeyatts && isleaf)
{
- lefthikey = _bt_truncate_tuple(rel, item);
+ lefthikey = _bt_nonkey_truncate(rel, item);
itemsz = IndexTupleSize(lefthikey);
itemsz = MAXALIGN(itemsz);
}
else
lefthikey = item;
+ Assert(BTreeTupleGetNAtts(lefthikey, rel) == indnkeyatts);
if (PageAddItem(leftpage, (Item) lefthikey, itemsz, leftoff,
false, false) == InvalidOffsetNumber)
{
@@ -1258,6 +1274,9 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
origpagenumber, RelationGetRelationName(rel));
}
leftoff = OffsetNumberNext(leftoff);
+ /* be tidy */
+ if (lefthikey != item)
+ pfree(lefthikey);
/*
* Now transfer all the data items to the appropriate page.
@@ -2143,7 +2162,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
left_item = (IndexTuple) palloc(left_item_sz);
left_item->t_info = left_item_sz;
BTreeInnerTupleSetDownLink(left_item, lbkno);
- BTreeTupSetNAtts(left_item, 0);
+ BTreeTupleSetNAtts(left_item, 0);
/*
* Create downlink item for right page. The key for it is obtained from
@@ -2180,6 +2199,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
* Note: we *must* insert the two items in item-number order, for the
* benefit of _bt_restore_page().
*/
+ Assert(BTreeTupleGetNAtts(left_item, rel) == 0);
if (PageAddItem(rootpage, (Item) left_item, left_item_sz, P_HIKEY,
false, false) == InvalidOffsetNumber)
elog(PANIC, "failed to add leftkey to new root page"
@@ -2189,6 +2209,8 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
/*
* insert the right page pointer into the new root page.
*/
+ Assert(BTreeTupleGetNAtts(right_item, rel) ==
+ IndexRelationGetNumberOfKeyAttributes(rel));
if (PageAddItem(rootpage, (Item) right_item, right_item_sz, P_FIRSTKEY,
false, false) == InvalidOffsetNumber)
elog(PANIC, "failed to add rightkey to new root page"
@@ -2284,7 +2306,7 @@ _bt_pgaddtup(Page page,
{
trunctuple = *itup;
trunctuple.t_info = sizeof(IndexTupleData);
- BTreeTupSetNAtts(&trunctuple, 0);
+ BTreeTupleSetNAtts(&trunctuple, 0);
itup = &trunctuple;
itemsize = sizeof(IndexTupleData);
}
@@ -2303,10 +2325,9 @@ _bt_pgaddtup(Page page,
* Rule is simple: NOT_NULL not equal NULL, NULL not equal NULL too.
*/
static bool
-_bt_isequal(Relation idxrel, Page page, OffsetNumber offnum,
+_bt_isequal(TupleDesc itupdesc, Page page, OffsetNumber offnum,
int keysz, ScanKey scankey)
{
- TupleDesc itupdesc = RelationGetDescr(idxrel);
IndexTuple itup;
int i;
@@ -2316,16 +2337,11 @@ _bt_isequal(Relation idxrel, Page page, OffsetNumber offnum,
itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, offnum));
/*
- * Index tuple shouldn't be truncated. Despite we technically could
- * compare truncated tuple as well, this function should be only called
- * for regular non-truncated leaf tuples and P_HIKEY tuple on
- * rightmost leaf page.
+ * It's okay that we might perform a comparison against a truncated page
+ * high key when caller needs to determine if _bt_check_unique scan must
+ * continue on to the next page. Caller never asks us to compare non-key
+ * attributes within an INCLUDE index.
*/
- Assert((P_RIGHTMOST((BTPageOpaque) PageGetSpecialPointer(page)) ||
- offnum != P_HIKEY)
- ? BTreeTupGetNAtts(itup, idxrel) == itupdesc->natts
- : true);
-
for (i = 1; i <= keysz; i++)
{
AttrNumber attno;
generated by cgit v1.2.3 (git 2.46.0) at 2025-09-30 04:55:01 +0000