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Re-use free space on index pages with duplicates.

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This commit is contained in:
Vadim B. Mikheev 1999-08-09 01:39:19 +00:00
parent 10d6d411a8
commit 1ecb43a40c
1 changed files with 9 additions and 20 deletions
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23
src/backend/access/nbtree/nbtinsert.c
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@ -7,7 +7,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.49 1999/07/19 07:07:19 momjian Exp $ * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.50 1999/08/09 01:39:19 vadim Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -392,17 +392,18 @@ _bt_insertonpg(Relation rel,
bool is_root = lpageop->btpo_flags & BTP_ROOT; bool is_root = lpageop->btpo_flags & BTP_ROOT;
/* /*
* If we have to split leaf page in the chain of duplicates by new * Instead of splitting leaf page in the chain of duplicates
* duplicate then we try to look at our right sibling first. * by new duplicate, insert it into some right page.
*/ */
if ((lpageop->btpo_flags & BTP_CHAIN) && if ((lpageop->btpo_flags & BTP_CHAIN) &&
(lpageop->btpo_flags & BTP_LEAF) && keys_equal) (lpageop->btpo_flags & BTP_LEAF) && keys_equal)
{ {
bool use_left = true;
rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE); rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE);
rpage = BufferGetPage(rbuf); rpage = BufferGetPage(rbuf);
rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage); rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage);
/*
* some checks
*/
if (!P_RIGHTMOST(rpageop)) /* non-rightmost page */ if (!P_RIGHTMOST(rpageop)) /* non-rightmost page */
{ /* If we have the same hikey here then { /* If we have the same hikey here then
* it's yet another page in chain. */ * it's yet another page in chain. */
@ -418,33 +419,21 @@ _bt_insertonpg(Relation rel,
BTGreaterStrategyNumber)) BTGreaterStrategyNumber))
elog(FATAL, "btree: hikey is out of order"); elog(FATAL, "btree: hikey is out of order");
else if (rpageop->btpo_flags & BTP_CHAIN) else if (rpageop->btpo_flags & BTP_CHAIN)
/* /*
* If hikey > scankey then it's last page in chain and * If hikey > scankey then it's last page in chain and
* BTP_CHAIN must be OFF * BTP_CHAIN must be OFF
*/ */
elog(FATAL, "btree: lost last page in the chain of duplicates"); elog(FATAL, "btree: lost last page in the chain of duplicates");
/* if there is room here then we use this page. */
if (PageGetFreeSpace(rpage) > itemsz)
use_left = false;
} }
else else
/* rightmost page */ /* rightmost page */
{ {
Assert(!(rpageop->btpo_flags & BTP_CHAIN)); Assert(!(rpageop->btpo_flags & BTP_CHAIN));
/* if there is room here then we use this page. */
if (PageGetFreeSpace(rpage) > itemsz)
use_left = false;
} }
if (!use_left) /* insert on the right page */
{
_bt_relbuf(rel, buf, BT_WRITE); _bt_relbuf(rel, buf, BT_WRITE);
return (_bt_insertonpg(rel, rbuf, stack, keysz, return (_bt_insertonpg(rel, rbuf, stack, keysz,
scankey, btitem, afteritem)); scankey, btitem, afteritem));
} }
_bt_relbuf(rel, rbuf, BT_WRITE);
}
/* /*
* If after splitting un-chained page we'll got chain of pages * If after splitting un-chained page we'll got chain of pages