diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/vdbe.c | 20 | ||||
| -rw-r--r-- | src/vdbeInt.h | 6 | ||||
| -rw-r--r-- | src/vdbeaux.c | 8 | ||||
| -rw-r--r-- | src/wherecode.c | 50 |
4 files changed, 76 insertions, 8 deletions
diff --git a/src/vdbe.c b/src/vdbe.c index cfff895c3..8ad1a17c3 100644 --- a/src/vdbe.c +++ b/src/vdbe.c @@ -2376,12 +2376,16 @@ case OP_Column: { u32 t; /* A type code from the record header */ Mem *pReg; /* PseudoTable input register */ + pC = p->apCsr[pOp->p1]; p2 = pOp->p2; + + /* If the cursor cache is stale, bring it up-to-date */ + rc = sqlite3VdbeCursorMoveto(&pC, &p2); + assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) ); pDest = &aMem[pOp->p3]; memAboutToChange(p, pDest); assert( pOp->p1>=0 && pOp->p1<p->nCursor ); - pC = p->apCsr[pOp->p1]; assert( pC!=0 ); assert( p2<pC->nField ); aOffset = pC->aOffset; @@ -2390,8 +2394,6 @@ case OP_Column: { assert( pC->eCurType!=CURTYPE_SORTER ); pCrsr = pC->uc.pCursor; - /* If the cursor cache is stale, bring it up-to-date */ - rc = sqlite3VdbeCursorMoveto(pC); if( rc ) goto abort_due_to_error; if( pC->cacheStatus!=p->cacheCtr ){ if( pC->nullRow ){ @@ -3846,7 +3848,7 @@ seek_not_found: break; } -/* Opcode: Seek P1 P2 * * * +/* Opcode: Seek P1 P2 P3 P4 * ** Synopsis: intkey=r[P2] ** ** P1 is an open table cursor and P2 is a rowid integer. Arrange @@ -3855,6 +3857,13 @@ seek_not_found: ** This is actually a deferred seek. Nothing actually happens until ** the cursor is used to read a record. That way, if no reads ** occur, no unnecessary I/O happens. +** +** P4 may contain an array of integers (type P4_INTARRAY) containing +** one entry for each column in the table P1 is open on. If so, then +** parameter P3 is a cursor open on a database index. If array entry +** a[i] is non-zero, then reading column (a[i]-1) from cursor P3 is +** equivalent to performing the deferred seek and then reading column i +** from P1. */ case OP_Seek: { /* in2 */ VdbeCursor *pC; @@ -3869,6 +3878,9 @@ case OP_Seek: { /* in2 */ pIn2 = &aMem[pOp->p2]; pC->movetoTarget = sqlite3VdbeIntValue(pIn2); pC->deferredMoveto = 1; + assert( pOp->p4type==P4_INTARRAY || pOp->p4.ai==0 ); + pC->aAltMap = pOp->p4.ai; + pC->pAltCursor = p->apCsr[pOp->p3]; break; } diff --git a/src/vdbeInt.h b/src/vdbeInt.h index b231cf908..e1c6d0656 100644 --- a/src/vdbeInt.h +++ b/src/vdbeInt.h @@ -74,6 +74,7 @@ typedef struct AuxData AuxData; ** * A virtual table ** * A one-row "pseudotable" stored in a single register */ +typedef struct VdbeCursor VdbeCursor; struct VdbeCursor { u8 eCurType; /* One of the CURTYPE_* values above */ i8 iDb; /* Index of cursor database in db->aDb[] (or -1) */ @@ -100,6 +101,8 @@ struct VdbeCursor { int seekResult; /* Result of previous sqlite3BtreeMoveto() */ i64 seqCount; /* Sequence counter */ i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */ + VdbeCursor *pAltCursor; /* Set by OP_Seek */ + int *aAltMap; /* Set by OP_Seek */ #ifdef SQLITE_ENABLE_COLUMN_USED_MASK u64 maskUsed; /* Mask of columns used by this cursor */ #endif @@ -124,7 +127,6 @@ struct VdbeCursor { ** static element declared in the structure. nField total array slots for ** aType[] and nField+1 array slots for aOffset[] */ }; -typedef struct VdbeCursor VdbeCursor; /* ** When a sub-program is executed (OP_Program), a structure of this type @@ -423,7 +425,7 @@ struct Vdbe { void sqlite3VdbeError(Vdbe*, const char *, ...); void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*); void sqliteVdbePopStack(Vdbe*,int); -int sqlite3VdbeCursorMoveto(VdbeCursor*); +int sqlite3VdbeCursorMoveto(VdbeCursor**, int*); int sqlite3VdbeCursorRestore(VdbeCursor*); #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE) void sqlite3VdbePrintOp(FILE*, int, Op*); diff --git a/src/vdbeaux.c b/src/vdbeaux.c index 3bbc5aad5..6e368cfdb 100644 --- a/src/vdbeaux.c +++ b/src/vdbeaux.c @@ -3008,9 +3008,15 @@ int sqlite3VdbeCursorRestore(VdbeCursor *p){ ** If the cursor is already pointing to the correct row and that row has ** not been deleted out from under the cursor, then this routine is a no-op. */ -int sqlite3VdbeCursorMoveto(VdbeCursor *p){ +int sqlite3VdbeCursorMoveto(VdbeCursor **pp, int *piCol){ + VdbeCursor *p = *pp; if( p->eCurType==CURTYPE_BTREE ){ if( p->deferredMoveto ){ + if( p->aAltMap && p->aAltMap[*piCol] ){ + *pp = p->pAltCursor; + *piCol = p->aAltMap[*piCol] - 1; + return SQLITE_OK; + } return handleDeferredMoveto(p); } if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){ diff --git a/src/wherecode.c b/src/wherecode.c index 4fd7399ef..eacd6d08d 100644 --- a/src/wherecode.c +++ b/src/wherecode.c @@ -747,6 +747,54 @@ static void codeCursorHint( #endif /* SQLITE_ENABLE_CURSOR_HINTS */ /* +** Cursor iCur is open on an intkey b-tree (a table). Register iRowid contains +** a rowid value just read from cursor iIdxCur, open on index pIdx. This +** function generates code to do a deferred seek of cursor iCur to the +** rowid stored in register iRowid. +** +** Normally, this is just: +** +** OP_Seek $iCur $iRowid +** +** However, if the scan currently being coded is a branch of an OR-loop and +** the statement currently being coded is a SELECT, then P3 of the OP_Seek +** is set to iIdxCur and P4 is set to point to an array of integers +** containing one entry for each column of the table cursor iCur is open +** on. For each table column, if the column is the i'th column of the +** index, then the corresponding array entry is set to (i+1). If the column +** does not appear in the index at all, the array entry is set to 0. +*/ +static void codeDeferredSeek( + WhereInfo *pWInfo, /* Where clause context */ + Index *pIdx, /* Index scan is using */ + int iCur, /* Cursor for IPK b-tree */ + int iRowid, /* Register containing rowid to seek to */ + int iIdxCur /* Index cursor */ +){ + Parse *pParse = pWInfo->pParse; /* Parse context */ + Vdbe *v = pParse->pVdbe; /* Vdbe to generate code within */ + + assert( iIdxCur>0 ); + assert( pIdx->aiColumn[pIdx->nColumn-1]==-1 ); + + sqlite3VdbeAddOp3(v, OP_Seek, iCur, iRowid, iIdxCur); + if( (pWInfo->wctrlFlags & WHERE_FORCE_TABLE) + && sqlite3ParseToplevel(pParse)->writeMask==0 + ){ + int i; + Table *pTab = pIdx->pTable; + int *ai = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int) * pTab->nCol); + if( ai ){ + for(i=0; i<pIdx->nColumn-1; i++){ + assert( pIdx->aiColumn[i]<pTab->nCol ); + if( pIdx->aiColumn[i]>=0 ) ai[pIdx->aiColumn[i]] = i+1; + } + sqlite3VdbeChangeP4(v, -1, (char*)ai, P4_INTARRAY); + } + } +} + +/* ** Generate code for the start of the iLevel-th loop in the WHERE clause ** implementation described by pWInfo. */ @@ -1232,7 +1280,7 @@ Bitmask sqlite3WhereCodeOneLoopStart( sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowidReg); VdbeCoverage(v); }else{ - sqlite3VdbeAddOp2(v, OP_Seek, iCur, iRowidReg); /* Deferred seek */ + codeDeferredSeek(pWInfo, pIdx, iCur, iRowidReg, iIdxCur); } }else if( iCur!=iIdxCur ){ Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable); |