Index: src/btree.c ================================================================== --- src/btree.c +++ src/btree.c @@ -4815,18 +4815,28 @@ /* ** Advance the cursor to the next entry in the database. If ** successful then set *pRes=0. If the cursor ** was already pointing to the last entry in the database before ** this routine was called, then set *pRes=1. +** +** The calling function will set *pRes to 0 or 1. The initial *pRes value +** will be 1 if the cursor being stepped corresponds to an SQL index and +** if this routine could have been skipped if that SQL index had been +** a unique index. Otherwise the caller will have set *pRes to zero. +** Zero is the common case. The btree implementation is free to use the +** initial *pRes value as a hint to improve performance, but the current +** SQLite btree implementation does not. (Note that the comdb2 btree +** implementation does use this hint, however.) */ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){ int rc; int idx; MemPage *pPage; assert( cursorHoldsMutex(pCur) ); assert( pRes!=0 ); + assert( *pRes==0 || *pRes==1 ); assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID ); if( pCur->eState!=CURSOR_VALID ){ rc = restoreCursorPosition(pCur); if( rc!=SQLITE_OK ){ *pRes = 0; @@ -4901,17 +4911,27 @@ /* ** Step the cursor to the back to the previous entry in the database. If ** successful then set *pRes=0. If the cursor ** was already pointing to the first entry in the database before ** this routine was called, then set *pRes=1. +** +** The calling function will set *pRes to 0 or 1. The initial *pRes value +** will be 1 if the cursor being stepped corresponds to an SQL index and +** if this routine could have been skipped if that SQL index had been +** a unique index. Otherwise the caller will have set *pRes to zero. +** Zero is the common case. The btree implementation is free to use the +** initial *pRes value as a hint to improve performance, but the current +** SQLite btree implementation does not. (Note that the comdb2 btree +** implementation does use this hint, however.) */ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){ int rc; MemPage *pPage; assert( cursorHoldsMutex(pCur) ); assert( pRes!=0 ); + assert( *pRes==0 || *pRes==1 ); assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID ); pCur->atLast = 0; if( pCur->eState!=CURSOR_VALID ){ if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){ rc = btreeRestoreCursorPosition(pCur); @@ -7148,11 +7168,11 @@ ** from the internal node. The 'previous' entry is used for this instead ** of the 'next' entry, as the previous entry is always a part of the ** sub-tree headed by the child page of the cell being deleted. This makes ** balancing the tree following the delete operation easier. */ if( !pPage->leaf ){ - int notUsed; + int notUsed = 0; rc = sqlite3BtreePrevious(pCur, ¬Used); if( rc ) return rc; } /* Save the positions of any other cursors open on this table before Index: src/vdbe.c ================================================================== --- src/vdbe.c +++ src/vdbe.c @@ -3578,19 +3578,21 @@ #ifdef SQLITE_TEST sqlite3_search_count++; #endif if( oc>=OP_SeekGe ){ assert( oc==OP_SeekGe || oc==OP_SeekGt ); if( res<0 || (res==0 && oc==OP_SeekGt) ){ + res = 0; rc = sqlite3BtreeNext(pC->pCursor, &res); if( rc!=SQLITE_OK ) goto abort_due_to_error; pC->rowidIsValid = 0; }else{ res = 0; } }else{ assert( oc==OP_SeekLt || oc==OP_SeekLe ); if( res>0 || (res==0 && oc==OP_SeekLt) ){ + res = 0; rc = sqlite3BtreePrevious(pC->pCursor, &res); if( rc!=SQLITE_OK ) goto abort_due_to_error; pC->rowidIsValid = 0; }else{ /* res might be negative because the table is empty. Check to @@ -4440,50 +4442,60 @@ pc = pOp->p2 - 1; } break; } -/* Opcode: Next P1 P2 * * P5 +/* Opcode: Next P1 P2 P3 * P5 ** ** Advance cursor P1 so that it points to the next key/data pair in its ** table or index. If there are no more key/value pairs then fall through ** to the following instruction. But if the cursor advance was successful, ** jump immediately to P2. ** ** The P1 cursor must be for a real table, not a pseudo-table. P1 must have ** been opened prior to this opcode or the program will segfault. +** +** The P3 value is a hint to the btree implementation. If P3==1, that +** means P1 is an SQL index and that this instruction could have been +** omitted if that index had been unique. P3 is usually 0. P3 is +** always either 0 or 1. ** ** P4 is always of type P4_ADVANCE. The function pointer points to ** sqlite3BtreeNext(). ** ** If P5 is positive and the jump is taken, then event counter ** number P5-1 in the prepared statement is incremented. ** ** See also: Prev, NextIfOpen */ -/* Opcode: NextIfOpen P1 P2 * * P5 +/* Opcode: NextIfOpen P1 P2 P3 * P5 ** ** This opcode works just like OP_Next except that if cursor P1 is not ** open it behaves a no-op. */ -/* Opcode: Prev P1 P2 * * P5 +/* Opcode: Prev P1 P2 P3 * P5 ** ** Back up cursor P1 so that it points to the previous key/data pair in its ** table or index. If there is no previous key/value pairs then fall through ** to the following instruction. But if the cursor backup was successful, ** jump immediately to P2. ** ** The P1 cursor must be for a real table, not a pseudo-table. If P1 is ** not open then the behavior is undefined. +** +** The P3 value is a hint to the btree implementation. If P3==1, that +** means P1 is an SQL index and that this instruction could have been +** omitted if that index had been unique. P3 is usually 0. P3 is +** always either 0 or 1. ** ** P4 is always of type P4_ADVANCE. The function pointer points to ** sqlite3BtreePrevious(). ** ** If P5 is positive and the jump is taken, then event counter ** number P5-1 in the prepared statement is incremented. */ -/* Opcode: PrevIfOpen P1 P2 * * P5 +/* Opcode: PrevIfOpen P1 P2 P3 * P5 ** ** This opcode works just like OP_Prev except that if cursor P1 is not ** open it behaves a no-op. */ case OP_SorterNext: { /* jump */ @@ -4501,13 +4513,16 @@ case OP_Prev: /* jump */ case OP_Next: /* jump */ assert( pOp->p1>=0 && pOp->p1nCursor ); assert( pOp->p5aCounter) ); pC = p->apCsr[pOp->p1]; + res = pOp->p3; assert( pC!=0 ); assert( pC->deferredMoveto==0 ); assert( pC->pCursor ); + assert( res==0 || (res==1 && pC->isTable==0) ); + testcase( res==1 ); assert( pOp->opcode!=OP_Next || pOp->p4.xAdvance==sqlite3BtreeNext ); assert( pOp->opcode!=OP_Prev || pOp->p4.xAdvance==sqlite3BtreePrevious ); assert( pOp->opcode!=OP_NextIfOpen || pOp->p4.xAdvance==sqlite3BtreeNext ); assert( pOp->opcode!=OP_PrevIfOpen || pOp->p4.xAdvance==sqlite3BtreePrevious); rc = pOp->p4.xAdvance(pC->pCursor, &res); Index: src/where.c ================================================================== --- src/where.c +++ src/where.c @@ -3180,10 +3180,12 @@ pLevel->op = OP_Prev; }else{ pLevel->op = OP_Next; } pLevel->p1 = iIdxCur; + assert( (WHERE_UNQ_WANTED>>16)==1 ); + pLevel->p3 = (pLoop->wsFlags>>16)&1; if( (pLoop->wsFlags & WHERE_CONSTRAINT)==0 ){ pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP; }else{ assert( pLevel->p5==0 ); } @@ -3976,16 +3978,17 @@ assert( (pNew->wsFlags & (WHERE_COLUMN_NULL|WHERE_COLUMN_IN|WHERE_SKIPSCAN))!=0 || nInMul==0 ); pNew->wsFlags |= WHERE_COLUMN_EQ; - if( iCol<0 - || (pProbe->onError!=OE_None && nInMul==0 - && pNew->u.btree.nEq==pProbe->nKeyCol-1) - ){ + if( iCol<0 || (nInMul==0 && pNew->u.btree.nEq==pProbe->nKeyCol-1)){ assert( (pNew->wsFlags & WHERE_COLUMN_IN)==0 || iCol<0 ); - pNew->wsFlags |= WHERE_ONEROW; + if( iCol>=0 && pProbe->onError==OE_None ){ + pNew->wsFlags |= WHERE_UNQ_WANTED; + }else{ + pNew->wsFlags |= WHERE_ONEROW; + } } pNew->u.btree.nEq++; pNew->nOut = nRowEst + nInMul; }else if( pTerm->eOperator & (WO_ISNULL) ){ pNew->wsFlags |= WHERE_COLUMN_NULL; @@ -5771,11 +5774,11 @@ int addr; pLevel = &pWInfo->a[i]; pLoop = pLevel->pWLoop; sqlite3VdbeResolveLabel(v, pLevel->addrCont); if( pLevel->op!=OP_Noop ){ - sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2); + sqlite3VdbeAddOp3(v, pLevel->op, pLevel->p1, pLevel->p2, pLevel->p3); sqlite3VdbeChangeP5(v, pLevel->p5); } if( pLoop->wsFlags & WHERE_IN_ABLE && pLevel->u.in.nIn>0 ){ struct InLoop *pIn; int j; Index: src/whereInt.h ================================================================== --- src/whereInt.h +++ src/whereInt.h @@ -68,11 +68,11 @@ int addrSkip; /* Jump here for next iteration of skip-scan */ int addrCont; /* Jump here to continue with the next loop cycle */ int addrFirst; /* First instruction of interior of the loop */ int addrBody; /* Beginning of the body of this loop */ u8 iFrom; /* Which entry in the FROM clause */ - u8 op, p5; /* Opcode and P5 of the opcode that ends the loop */ + u8 op, p3, p5; /* Opcode, P3 & P5 of the opcode that ends the loop */ int p1, p2; /* Operands of the opcode used to ends the loop */ union { /* Information that depends on pWLoop->wsFlags */ struct { int nIn; /* Number of entries in aInLoop[] */ struct InLoop { @@ -455,5 +455,6 @@ #define WHERE_IN_ABLE 0x00000800 /* Able to support an IN operator */ #define WHERE_ONEROW 0x00001000 /* Selects no more than one row */ #define WHERE_MULTI_OR 0x00002000 /* OR using multiple indices */ #define WHERE_AUTO_INDEX 0x00004000 /* Uses an ephemeral index */ #define WHERE_SKIPSCAN 0x00008000 /* Uses the skip-scan algorithm */ +#define WHERE_UNQ_WANTED 0x00010000 /* WHERE_ONEROW would have been helpful*/