database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-08-05 15:55:57 +03:00
Code Activity

Improve the strict enforcement of cell sizes in balancing from

Browse Source 
check-in [12713f320b2c1def] so that it also works with table-btrees
in addition to index-btrees.

FossilOrigin-Name: ef27e7a08728aa7447ae19812803ac5c4a9d80c97541014bd292485792005a3e
This commit is contained in:
drh
2019-02-01 14:50:43 +00:00
parent 1c7d389a23
commit 26b7ec8b24
3 changed files with 32 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
src/btree.c
View File

@@ -6728,7 +6728,7 @@ static void insertCell(
** |Child-1| |Child-2| |Child-3|
** --------- --------- ---------
**
** The order of cells is in the array is:
** The order of cells is in the array is for an index btree is:
**
** 1. All cells from Child-1 in order
** 2. The first divider cell from Parent
@@ -6736,15 +6736,26 @@ static void insertCell(
** 4. The second divider cell from Parent
** 5. All cells from Child-3 in order
**
** The apEnd[] array holds pointer to the end of page for Child-1, the
** Parent, Child-2, the Parent (again), and Child-3. The ixNx[] array
** holds the number of cells contained in each of these 5 stages, and
** all stages to the left. Hence:
** For a table-btree (with rowids) the items 2 and 4 are empty because
** content exists only in leaves and there are no divider cells.
**
** For an index btree, the apEnd[] array holds pointer to the end of page
** for Child-1, the Parent, Child-2, the Parent (again), and Child-3,
** respectively. The ixNx[] array holds the number of cells contained in
** each of these 5 stages, and all stages to the left. Hence:
**
** ixNx[0] = Number of cells in Child-1.
** ixNx[1] = Number of cells in Child-1 plus 1 for first divider.
** ixNx[2] = Number of cells in Child-1 and Child-2 + 1 for 1st divider.
** ixNx[3] = Number of cells in Child-1 and Child-2 + both divider cells
** ixNx[4] = Total number of cells.
**
** For a table-btree, the concept is similar, except only apEnd[0]..apEnd[2]
** are used and they point to the leaf pages only, and the ixNx value are:
**
** ixNx[0] = Number of cells in Child-1.
** ixNx[1] = Number of cells in Child-1 and Child-2 + 1 for 1st divider.
** ixNx[2] = Number of cells in Child-1 and Child-2 + both divider cells
*/
typedef struct CellArray CellArray;
struct CellArray {
@@ -7658,12 +7669,15 @@ static int balance_nonroot(
**
*/
usableSpace = pBt->usableSize - 12 + leafCorrection;
for(i=0; i<nOld; i++){
for(i=k=0; i<nOld; i++, k++){
MemPage *p = apOld[i];
b.apEnd[i*2] = p->aDataEnd;
b.apEnd[i*2+1] = pParent->aDataEnd;
b.ixNx[i*2] = cntOld[i];
b.ixNx[i*2+1] = cntOld[i]+1;
b.apEnd[k] = p->aDataEnd;
b.ixNx[k] = cntOld[i];
if( !leafData ){
k++;
b.apEnd[k] = pParent->aDataEnd;
b.ixNx[k] = cntOld[i]+1;
}
szNew[i] = usableSpace - p->nFree;
for(j=0; j<p->nOverflow; j++){
szNew[i] += 2 + p->xCellSize(p, p->apOvfl[j]);