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If a table has one or more rows and it has a partial index has zero rows,

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still make an entry in the sqlite_stat1 table for the partial index, so that
we know that "PRAGMA optimize" does not need to redo the whole table.

FossilOrigin-Name: e147b18991dd462fff367442acb0504fdf193a31843ed34ec8c1ced30747bf8a
This commit is contained in:
drh
2024-02-19 16:22:58 +00:00
parent 6c6356f7f2
commit e7bdb2172c
7 changed files with 70 additions and 59 deletions
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74
src/analyze.c
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@@ -872,7 +872,7 @@ static void statGet(
if( iVal==2 && p->nRow*10 <= nDistinct*11 ) iVal = 1;
sqlite3_str_appendf(&sStat, " %llu", iVal);
#ifdef SQLITE_ENABLE_STAT4
assert( p->current.anEq[i] );
assert( p->current.anEq[i] || p->nRow==0 );
#endif
}
sqlite3ResultStrAccum(context, &sStat);
@@ -1057,7 +1057,7 @@ static void analyzeOneTable(
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int nCol; /* Number of columns in pIdx. "N" */
int addrRewind; /* Address of "OP_Rewind iIdxCur" */
int addrGotoEnd; /* Address of "OP_Rewind iIdxCur" */
int addrNextRow; /* Address of "next_row:" */
const char *zIdxName; /* Name of the index */
int nColTest; /* Number of columns to test for changes */
@@ -1081,9 +1081,14 @@ static void analyzeOneTable(
/*
** Pseudo-code for loop that calls stat_push():
**
** Rewind csr
** if eof(csr) goto end_of_scan;
** regChng = 0
** Rewind csr
** if eof(csr){
** stat_init() with count = 0;
** goto end_of_scan;
** }
** count()
** stat_init()
** goto chng_addr_0;
**
** next_row:
@@ -1122,41 +1127,36 @@ static void analyzeOneTable(
sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
VdbeComment((v, "%s", pIdx->zName));
/* Invoke the stat_init() function. The arguments are:
**
/* Implementation of the following:
**
** regChng = 0
** Rewind csr
** if eof(csr){
** stat_init() with count = 0;
** goto end_of_scan;
** }
** count()
** stat_init()
** goto chng_addr_0;
*/
assert( regTemp2==regStat+4 );
sqlite3VdbeAddOp2(v, OP_Integer, db->nAnalysisLimit, regTemp2);
/* Arguments to stat_init():
** (1) the number of columns in the index including the rowid
** (or for a WITHOUT ROWID table, the number of PK columns),
** (2) the number of columns in the key without the rowid/pk
** (3) estimated number of rows in the index,
*/
** (3) estimated number of rows in the index. */
sqlite3VdbeAddOp2(v, OP_Integer, nCol, regStat+1);
assert( regRowid==regStat+2 );
sqlite3VdbeAddOp2(v, OP_Integer, pIdx->nKeyCol, regRowid);
#ifdef SQLITE_ENABLE_STAT4
if( OptimizationEnabled(db, SQLITE_Stat4) ){
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regTemp);
addrRewind = sqlite3VdbeAddOp1(v, OP_Rewind, iIdxCur);
VdbeCoverage(v);
}else
#endif
{
addrRewind = sqlite3VdbeAddOp1(v, OP_Rewind, iIdxCur);
VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_Count, iIdxCur, regTemp, 1);
}
assert( regTemp2==regStat+4 );
sqlite3VdbeAddOp2(v, OP_Integer, db->nAnalysisLimit, regTemp2);
sqlite3VdbeAddOp3(v, OP_Count, iIdxCur, regTemp,
OptimizationDisabled(db, SQLITE_Stat4));
sqlite3VdbeAddFunctionCall(pParse, 0, regStat+1, regStat, 4,
&statInitFuncdef, 0);
addrGotoEnd = sqlite3VdbeAddOp1(v, OP_Rewind, iIdxCur);
VdbeCoverage(v);
/* Implementation of the following:
**
** Rewind csr
** if eof(csr) goto end_of_scan;
** regChng = 0
** goto next_push_0;
**
*/
sqlite3VdbeAddOp2(v, OP_Integer, 0, regChng);
addrNextRow = sqlite3VdbeCurrentAddr(v);
@@ -1263,6 +1263,12 @@ static void analyzeOneTable(
}
/* Add the entry to the stat1 table. */
if( pIdx->pPartIdxWhere ){
/* Partial indexes might get a zero-entry in sqlite_stat1. But
** an empty table is omitted from sqlite_stat1. */
sqlite3VdbeJumpHere(v, addrGotoEnd);
addrGotoEnd = 0;
}
callStatGet(pParse, regStat, STAT_GET_STAT1, regStat1);
assert( "BBB"[0]==SQLITE_AFF_TEXT );
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "BBB", 0);
@@ -1286,6 +1292,12 @@ static void analyzeOneTable(
int addrIsNull;
u8 seekOp = HasRowid(pTab) ? OP_NotExists : OP_NotFound;
/* No STAT4 data is generated if the number of rows is zero */
if( addrGotoEnd==0 ){
sqlite3VdbeAddOp2(v, OP_Cast, regStat1, SQLITE_AFF_INTEGER);
addrGotoEnd = sqlite3VdbeAddOp1(v, OP_IfNot, regStat1);
}
if( doOnce ){
int mxCol = nCol;
Index *pX;
@@ -1338,7 +1350,7 @@ static void analyzeOneTable(
#endif /* SQLITE_ENABLE_STAT4 */
/* End of analysis */
sqlite3VdbeJumpHere(v, addrRewind);
if( addrGotoEnd ) sqlite3VdbeJumpHere(v, addrGotoEnd);
}