Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
Comment: | Reduce the memory required by prepared statements that use the IN operator with a list on the right and an INTEGER PRIMARY KEY on the left. |
---|---|
Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
e7984ad2f7e4be30e7198ebd6609a7f6 |
User & Date: | drh 2009-10-29 13:48:11.000 |
Context
2009-10-30
| ||
13:25 | Avoid storing the result register for EXISTS and SELECT in any field of the Expr object - simply return the register number as the return value of the function that codes those expressions. (check-in: 7253f8fad1 user: drh tags: trunk) | |
2009-10-29
| ||
13:48 | Reduce the memory required by prepared statements that use the IN operator with a list on the right and an INTEGER PRIMARY KEY on the left. (check-in: e7984ad2f7 user: drh tags: trunk) | |
2009-10-27
| ||
18:06 | Minor updates and corrections to comments in btreeInt.h. No changes to code. (check-in: ad949fa1ac user: drh tags: trunk) | |
Changes
Changes to src/expr.c.
︙ | ︙ | |||
1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 | /* Loop through each expression in <exprlist>. */ r1 = sqlite3GetTempReg(pParse); r2 = sqlite3GetTempReg(pParse); sqlite3VdbeAddOp2(v, OP_Null, 0, r2); for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){ Expr *pE2 = pItem->pExpr; /* If the expression is not constant then we will need to ** disable the test that was generated above that makes sure ** this code only executes once. Because for a non-constant ** expression we need to rerun this code each time. */ if( testAddr && !sqlite3ExprIsConstant(pE2) ){ sqlite3VdbeChangeToNoop(v, testAddr-1, 2); testAddr = 0; } /* Evaluate the expression and insert it into the temp table */ | > > > > | | | > | | | | | > | 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 | /* Loop through each expression in <exprlist>. */ r1 = sqlite3GetTempReg(pParse); r2 = sqlite3GetTempReg(pParse); sqlite3VdbeAddOp2(v, OP_Null, 0, r2); for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){ Expr *pE2 = pItem->pExpr; int iValToIns; /* If the expression is not constant then we will need to ** disable the test that was generated above that makes sure ** this code only executes once. Because for a non-constant ** expression we need to rerun this code each time. */ if( testAddr && !sqlite3ExprIsConstant(pE2) ){ sqlite3VdbeChangeToNoop(v, testAddr-1, 2); testAddr = 0; } /* Evaluate the expression and insert it into the temp table */ if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){ sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns); }else{ r3 = sqlite3ExprCodeTarget(pParse, pE2, r1); if( isRowid ){ sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, sqlite3VdbeCurrentAddr(v)+2); sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3); }else{ sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1); sqlite3ExprCacheAffinityChange(pParse, r3, 1); sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2); } } } sqlite3ReleaseTempReg(pParse, r1); sqlite3ReleaseTempReg(pParse, r2); } if( !isRowid ){ sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO); |
︙ | ︙ | |||
2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 | ** factoring out of a loop, then evaluate the expression ** into a register and convert the expression into a TK_REGISTER ** expression. */ static int evalConstExpr(Walker *pWalker, Expr *pExpr){ Parse *pParse = pWalker->pParse; switch( pExpr->op ){ case TK_REGISTER: { return WRC_Prune; } case TK_FUNCTION: case TK_AGG_FUNCTION: case TK_CONST_FUNC: { /* The arguments to a function have a fixed destination. | > | 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 | ** factoring out of a loop, then evaluate the expression ** into a register and convert the expression into a TK_REGISTER ** expression. */ static int evalConstExpr(Walker *pWalker, Expr *pExpr){ Parse *pParse = pWalker->pParse; switch( pExpr->op ){ case TK_IN: case TK_REGISTER: { return WRC_Prune; } case TK_FUNCTION: case TK_AGG_FUNCTION: case TK_CONST_FUNC: { /* The arguments to a function have a fixed destination. |
︙ | ︙ |
Changes to src/vdbe.c.
︙ | ︙ | |||
3754 3755 3756 3757 3758 3759 3760 | ** and register P2 becomes ephemeral. If the cursor is changed, the ** value of register P2 will then change. Make sure this does not ** cause any problems.) ** ** This instruction only works on tables. The equivalent instruction ** for indices is OP_IdxInsert. */ | > > > > > > | < < > > > > | > > > > | | | | 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 | ** and register P2 becomes ephemeral. If the cursor is changed, the ** value of register P2 will then change. Make sure this does not ** cause any problems.) ** ** This instruction only works on tables. The equivalent instruction ** for indices is OP_IdxInsert. */ /* Opcode: InsertInt P1 P2 P3 P4 P5 ** ** This works exactly like OP_Insert except that the key is the ** integer value P3, not the value of the integer stored in register P3. */ case OP_Insert: case OP_InsertInt: { Mem *pData; /* MEM cell holding data for the record to be inserted */ Mem *pKey; /* MEM cell holding key for the record */ i64 iKey; /* The integer ROWID or key for the record to be inserted */ VdbeCursor *pC; /* Cursor to table into which insert is written */ int nZero; /* Number of zero-bytes to append */ int seekResult; /* Result of prior seek or 0 if no USESEEKRESULT flag */ const char *zDb; /* database name - used by the update hook */ const char *zTbl; /* Table name - used by the opdate hook */ int op; /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */ pData = &p->aMem[pOp->p2]; assert( pOp->p1>=0 && pOp->p1<p->nCursor ); pC = p->apCsr[pOp->p1]; assert( pC!=0 ); assert( pC->pCursor!=0 ); assert( pC->pseudoTableReg==0 ); assert( pC->isTable ); REGISTER_TRACE(pOp->p2, pData); if( pOp->opcode==OP_Insert ){ pKey = &p->aMem[pOp->p3]; assert( pKey->flags & MEM_Int ); REGISTER_TRACE(pOp->p3, pKey); iKey = pKey->u.i; }else{ assert( pOp->opcode==OP_InsertInt ); iKey = pOp->p3; } if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++; if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = iKey; if( pData->flags & MEM_Null ){ pData->z = 0; pData->n = 0; }else{ assert( pData->flags & (MEM_Blob|MEM_Str) ); } seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0); |
︙ | ︙ |