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If we have to split leaf page in the chain of duplicates

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then we try to look at our right sibling first, but not farther,
as it was in yesterday fix.
This commit is contained in:
Vadim B. Mikheev 1997-05-31 06:35:56 +00:00
parent 5cf55737a4
commit 139858e699
1 changed files with 24 additions and 41 deletions
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45
src/backend/access/nbtree/nbtinsert.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.13 1997/05/30 18:35:31 vadim Exp $
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.14 1997/05/31 06:35:56 vadim Exp $
*
*-------------------------------------------------------------------------
*/
@ -287,30 +287,21 @@ _bt_insertonpg(Relation rel,
/*
* If we have to split leaf page in the chain of duplicates
* then we try to move righter to avoid splitting.
* then we try to look at our right sibling first.
*/
if ( ( lpageop->btpo_flags & BTP_CHAIN ) &&
( lpageop->btpo_flags & BTP_LEAF ) )
{
bool use_left = true;
for ( ; ; )
{
bool keys_equal = false;
rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE);
rpage = BufferGetPage(rbuf);
rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage);
if ( P_RIGHTMOST (rpageop) )
{
Assert ( !( rpageop->btpo_flags & BTP_CHAIN ) );
use_left = false;
break;
}
/*
if ( !P_RIGHTMOST (rpageop) ) /* non-rightmost page */
{ /*
* If we have the same hikey here then it's
* yet another page in chain and we may move
* even righter.
* yet another page in chain.
*/
if ( _bt_skeycmp (rel, keysz, scankey, rpage,
PageGetItemId(rpage, P_HIKEY),
@ -336,26 +327,19 @@ _bt_insertonpg(Relation rel,
BTItem tmp;
lpageop->btpo_flags &= ~BTP_CHAIN;
tmp = (BTItem) PageGetItem(rpage,
PageGetItemId(rpage, P_HIKEY));
tmp = (BTItem) PageGetItem(rpage, PageGetItemId(rpage, P_HIKEY));
hiRightItem = _bt_formitem(&(tmp->bti_itup));
break;
}
/*
* if there is room here or hikey > scankey (so it's our
* last page in the chain and we can't move righter)
* we have to use this page .
*/
if ( PageGetFreeSpace (rpage) > itemsz || !keys_equal )
{
/* if there is room here then we use this page. */
else if ( PageGetFreeSpace (rpage) > itemsz )
use_left = false;
break;
}
/* try to move righter */
_bt_relbuf(rel, buf, BT_WRITE);
buf = rbuf;
page = rpage;
lpageop = rpageop;
else /* rightmost page */
{
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 */
{
@ -364,7 +348,6 @@ _bt_insertonpg(Relation rel,
scankey, btitem, afteritem) );
}
_bt_relbuf(rel, rbuf, BT_WRITE);
bknum = BufferGetBlockNumber(buf);
}
/* split the buffer into left and right halves */