*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.7 1996/11/13 20:47:11 scrappy Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.8 1996/12/06 09:45:30 vadim Exp $
*
*-------------------------------------------------------------------------
*/
static void _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf);
static OffsetNumber _bt_pgaddtup(Relation rel, Buffer buf, int keysz, ScanKey itup_scankey, Size itemsize, BTItem btitem, BTItem afteritem);
static bool _bt_goesonpg(Relation rel, Buffer buf, Size keysz, ScanKey scankey, BTItem afteritem);
-
-#if 0
static void _bt_updateitem(Relation rel, Size keysz, Buffer buf, Oid bti_oid, BTItem newItem);
-#endif
/*
* _bt_doinsert() -- Handle insertion of a single btitem in the tree.
if (_bt_itemcmp(rel, keysz, stack->bts_btitem, new_item,
BTGreaterStrategyNumber)) {
+ ppageop = (BTPageOpaque) PageGetSpecialPointer(page);
+ Assert (P_LEFTMOST(ppageop));
lowLeftItem =
(BTItem) PageGetItem(page,
PageGetItemId(page, P_FIRSTKEY));
/* because it's bigger than what was there before). */
/* --djm 8/21/96 */
- /* _bt_updateitem(rel, keysz, pbuf, stack->bts_btitem->bti_oid,
- lowLeftItem); */
-
- /* get the parent page */
- ppage = BufferGetPage(pbuf);
- ppageop = (BTPageOpaque) PageGetSpecialPointer(ppage);
+ /*
+ * but it works for items with the same size and so why don't
+ * use it for them ? - vadim 12/05/96
+ */
+ if ( DOUBLEALIGN (IndexTupleDSize (lowLeftItem->bti_itup)) ==
+ DOUBLEALIGN (IndexTupleDSize (stack->bts_btitem->bti_itup)) )
+ {
+ _bt_updateitem(rel, keysz, pbuf,
+ stack->bts_btitem->bti_oid, lowLeftItem);
+ _bt_relbuf(rel, buf, BT_WRITE);
+ _bt_relbuf(rel, rbuf, BT_WRITE);
+ }
+ else
+ {
+ /* get the parent page */
+ ppage = BufferGetPage(pbuf);
+ ppageop = (BTPageOpaque) PageGetSpecialPointer(ppage);
- /* figure out which key is leftmost (if the parent page */
- /* is rightmost, too, it must be the root) */
- if(P_RIGHTMOST(ppageop)) {
- leftmost_offset = P_HIKEY;
- } else {
- leftmost_offset = P_FIRSTKEY;
- }
- PageIndexTupleDelete(ppage, leftmost_offset);
+ /*
+ * figure out which key is leftmost (if the parent page
+ * is rightmost, too, it must be the root)
+ */
+ if(P_RIGHTMOST(ppageop)) {
+ leftmost_offset = P_HIKEY;
+ } else {
+ leftmost_offset = P_FIRSTKEY;
+ }
+ PageIndexTupleDelete(ppage, leftmost_offset);
- /* don't write anything out yet--we still have the write */
- /* lock, and now we call another _bt_insertonpg to */
- /* insert the correct leftmost key */
+ /*
+ * don't write anything out yet--we still have the write
+ * lock, and now we call another _bt_insertonpg to
+ * insert the correct leftmost key
+ */
- /* make a new leftmost item, using the tuple data from */
- /* lowLeftItem. point it to the left child. */
- /* update it on the stack at the same time. */
- bknum = BufferGetBlockNumber(buf);
- pfree(stack->bts_btitem);
- stack->bts_btitem = _bt_formitem(&(lowLeftItem->bti_itup));
- ItemPointerSet(&(stack->bts_btitem->bti_itup.t_tid),
+ /*
+ * make a new leftmost item, using the tuple data from
+ * lowLeftItem. point it to the left child.
+ * update it on the stack at the same time.
+ */
+ bknum = BufferGetBlockNumber(buf);
+ pfree(stack->bts_btitem);
+ stack->bts_btitem = _bt_formitem(&(lowLeftItem->bti_itup));
+ ItemPointerSet(&(stack->bts_btitem->bti_itup.t_tid),
bknum, P_HIKEY);
- /* unlock the children before doing this */
- _bt_relbuf(rel, buf, BT_WRITE);
- _bt_relbuf(rel, rbuf, BT_WRITE);
+ /* unlock the children before doing this */
+ _bt_relbuf(rel, buf, BT_WRITE);
+ _bt_relbuf(rel, rbuf, BT_WRITE);
- /* a regular _bt_binsrch should find the right place to */
- /* put the new entry, since it should be lower than any */
- /* other key on the page, therefore set afteritem to NULL */
- newskey = _bt_mkscankey(rel, &(stack->bts_btitem->bti_itup));
- newres = _bt_insertonpg(rel, pbuf, stack->bts_parent,
+ /*
+ * a regular _bt_binsrch should find the right place to
+ * put the new entry, since it should be lower than any
+ * other key on the page, therefore set afteritem to NULL
+ */
+ newskey = _bt_mkscankey(rel, &(stack->bts_btitem->bti_itup));
+ newres = _bt_insertonpg(rel, pbuf, stack->bts_parent,
keysz, newskey, stack->bts_btitem,
NULL);
- pfree(newres);
- pfree(newskey);
+ pfree(newres);
+ pfree(newskey);
- /* we have now lost our lock on the parent buffer, and */
- /* need to get it back. */
- pbuf = _bt_getstackbuf(rel, stack, BT_WRITE);
- } else {
- _bt_relbuf(rel, buf, BT_WRITE);
- _bt_relbuf(rel, rbuf, BT_WRITE);
+ /*
+ * we have now lost our lock on the parent buffer, and
+ * need to get it back.
+ */
+ pbuf = _bt_getstackbuf(rel, stack, BT_WRITE);
+ }
+ }
+ else
+ {
+ _bt_relbuf(rel, buf, BT_WRITE);
+ _bt_relbuf(rel, rbuf, BT_WRITE);
}
newskey = _bt_mkscankey(rel, &(new_item->bti_itup));
return (true);
}
-#if 0
-/* gone since updating in place doesn't work in general --djm 11/13/96 */
/*
* _bt_updateitem() -- updates the key of the item identified by the
* oid with the key of newItem (done in place if
elog(FATAL, "_bt_getstackbuf was lying!!");
}
+ /*
+ * It's defined by caller (_bt_insertonpg)
+ */
+ /*
if(IndexTupleDSize(newItem->bti_itup) >
IndexTupleDSize(item->bti_itup)) {
elog(NOTICE, "trying to overwrite a smaller value with a bigger one in _bt_updateitem");
elog(WARN, "this is not good.");
}
+ */
oldIndexTuple = &(item->bti_itup);
newIndexTuple = &(newItem->bti_itup);
/* keep the original item pointer */
- ItemPointerCopy(&(oldIndexTuple->t_tid), &itemPtrData);
- CopyIndexTuple(newIndexTuple, &oldIndexTuple);
- ItemPointerCopy(&itemPtrData, &(oldIndexTuple->t_tid));
+ ItemPointerCopy(&(oldIndexTuple->t_tid), &itemPtrData);
+ CopyIndexTuple(newIndexTuple, &oldIndexTuple);
+ ItemPointerCopy(&itemPtrData, &(oldIndexTuple->t_tid));
+
}
-#endif
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