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Another optimization to the btree logic. (CVS 811)

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FossilOrigin-Name: 03d20673616cae0dca524fd04557798a98fb7069
This commit is contained in:
drh
2003-01-04 18:53:27 +00:00
parent 428ae8cb41
commit bb49aba82a
3 changed files with 20 additions and 22 deletions
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28
src/btree.c
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@@ -9,7 +9,7 @@
** May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.77 2003/01/04 16:48:09 drh Exp $
** $Id: btree.c,v 1.78 2003/01/04 18:53:28 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
@@ -2123,7 +2123,6 @@ static int balance(Btree *pBt, MemPage *pPage, BtCursor *pCur){
int cntNew[4]; /* Index in apCell[] of cell after i-th page */
int szNew[4]; /* Combined size of cells place on i-th page */
MemPage *extraUnref = 0; /* A page that needs to be unref-ed */
Pgno pgno, swabPgno; /* Page number */
Cell *apCell[MX_CELL*3+5]; /* All cells from pages being balanceed */
int szCell[MX_CELL*3+5]; /* Local size of all cells */
Cell aTemp[2]; /* Temporary holding area for apDiv[] */
@@ -2198,7 +2197,7 @@ static int balance(Btree *pBt, MemPage *pPage, BtCursor *pCur){
assert( sqlitepager_iswriteable(pChild) );
copyPage(pChild, pPage);
pChild->pParent = pPage;
pChild->idxParent = pChild->nCell;
pChild->idxParent = 0;
sqlitepager_ref(pPage);
pChild->isOverfull = 1;
if( pCur && pCur->pPage==pPage ){
@@ -2221,20 +2220,19 @@ static int balance(Btree *pBt, MemPage *pPage, BtCursor *pCur){
** to pPage. The "idx" variable is the index of that cell. If pPage
** is the rightmost child of pParent then set idx to pParent->nCell
*/
idx = -1;
pgno = sqlitepager_pagenumber(pPage);
swabPgno = SWAB32(pBt, pgno);
for(i=0; i<pParent->nCell; i++){
if( pParent->apCell[i]->h.leftChild==swabPgno ){
idx = i;
break;
if( pParent->idxShift ){
Pgno pgno, swabPgno;
pgno = sqlitepager_pagenumber(pPage);
swabPgno = SWAB32(pBt, pgno);
for(idx=0; idx<pParent->nCell; idx++){
if( pParent->apCell[idx]->h.leftChild==swabPgno ){
break;
}
}
assert( idx<pParent->nCell || pParent->u.hdr.rightChild==swabPgno );
}else{
idx = pPage->idxParent;
}
if( idx<0 && pParent->u.hdr.rightChild==swabPgno ){
idx = pParent->nCell;
}
assert( idx>=0 );
/* assert( pParent->idxShift || idx==pPage->idxParent ); */
/*
** Initialize variables so that it will be safe to jump