diff options
Diffstat (limited to 'src/analyze.c')
| -rw-r--r-- | src/analyze.c | 95 |
1 files changed, 56 insertions, 39 deletions
diff --git a/src/analyze.c b/src/analyze.c index 59e3d9837..fc8680d78 100644 --- a/src/analyze.c +++ b/src/analyze.c @@ -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 +1292,13 @@ 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); + VdbeCoverage(v); + } + if( doOnce ){ int mxCol = nCol; Index *pX; @@ -1338,7 +1351,7 @@ static void analyzeOneTable( #endif /* SQLITE_ENABLE_STAT4 */ /* End of analysis */ - sqlite3VdbeJumpHere(v, addrRewind); + if( addrGotoEnd ) sqlite3VdbeJumpHere(v, addrGotoEnd); } @@ -1784,12 +1797,13 @@ static int loadStatTbl( while( sqlite3_step(pStmt)==SQLITE_ROW ){ int nIdxCol = 1; /* Number of columns in stat4 records */ - char *zIndex; /* Index name */ - Index *pIdx; /* Pointer to the index object */ - int nSample; /* Number of samples */ - int nByte; /* Bytes of space required */ - int i; /* Bytes of space required */ - tRowcnt *pSpace; + char *zIndex; /* Index name */ + Index *pIdx; /* Pointer to the index object */ + int nSample; /* Number of samples */ + int nByte; /* Bytes of space required */ + int i; /* Bytes of space required */ + tRowcnt *pSpace; /* Available allocated memory space */ + u8 *pPtr; /* Available memory as a u8 for easier manipulation */ zIndex = (char *)sqlite3_column_text(pStmt, 0); if( zIndex==0 ) continue; @@ -1809,7 +1823,7 @@ static int loadStatTbl( } pIdx->nSampleCol = nIdxCol; pIdx->mxSample = nSample; - nByte = sizeof(IndexSample) * nSample; + nByte = ROUND8(sizeof(IndexSample) * nSample); nByte += sizeof(tRowcnt) * nIdxCol * 3 * nSample; nByte += nIdxCol * sizeof(tRowcnt); /* Space for Index.aAvgEq[] */ @@ -1818,7 +1832,10 @@ static int loadStatTbl( sqlite3_finalize(pStmt); return SQLITE_NOMEM_BKPT; } - pSpace = (tRowcnt*)&pIdx->aSample[nSample]; + pPtr = (u8*)pIdx->aSample; + pPtr += ROUND8(nSample*sizeof(pIdx->aSample[0])); + pSpace = (tRowcnt*)pPtr; + assert( EIGHT_BYTE_ALIGNMENT( pSpace ) ); pIdx->aAvgEq = pSpace; pSpace += nIdxCol; pIdx->pTable->tabFlags |= TF_HasStat4; for(i=0; i<nSample; i++){ |