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Overview
Comment:Experimental code that tries to put the computation of subqueries inside a subroutine, and reuse that subroutine if the same subquery is evaluated more than once. Current code does not work for CHECK constraints.
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SHA3-256: 6c44838adbe5dc482bc010e91a6dd7a0f777c989f443dd600740d2c783208e0d
User & Date: drh 2018-12-24 02:34:49.752
Context
2018-12-24
11:55
Prevent the use of subroutines to implement the RHS of IN operators within CHECK constraints. (check-in: 6b24d3fb94 user: drh tags: reuse-subqueries)
02:34
Experimental code that tries to put the computation of subqueries inside a subroutine, and reuse that subroutine if the same subquery is evaluated more than once. Current code does not work for CHECK constraints. (check-in: 6c44838adb user: drh tags: reuse-subqueries)
2018-12-23
21:27
Split the code generation for the RHS of IN operators and for SELECT and EXISTS expressions into two separate subroutines, because there is now little commonality between those to functions. This is intended to help make the code easier to read and maintain. (check-in: 2b6494b150 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/expr.c.
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*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3FindInIndex(
  Parse *pParse,             /* Parsing context */
  Expr *pX,                  /* The right-hand side (RHS) of the IN operator */
  u32 inFlags,               /* IN_INDEX_LOOP, _MEMBERSHIP, and/or _NOOP_OK */
  int *prRhsHasNull,         /* Register holding NULL status.  See notes */
  int *aiMap                 /* Mapping from Index fields to RHS fields */

){
  Select *p;                            /* SELECT to the right of IN operator */
  int eType = 0;                        /* Type of RHS table. IN_INDEX_* */
  int iTab = pParse->nTab++;            /* Cursor of the RHS table */
  int mustBeUnique;                     /* True if RHS must be unique */
  Vdbe *v = sqlite3GetVdbe(pParse);     /* Virtual machine being coded */








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*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3FindInIndex(
  Parse *pParse,             /* Parsing context */
  Expr *pX,                  /* The right-hand side (RHS) of the IN operator */
  u32 inFlags,               /* IN_INDEX_LOOP, _MEMBERSHIP, and/or _NOOP_OK */
  int *prRhsHasNull,         /* Register holding NULL status.  See notes */
  int *aiMap,                /* Mapping from Index fields to RHS fields */
  int *piTab                 /* OUT: index to use */
){
  Select *p;                            /* SELECT to the right of IN operator */
  int eType = 0;                        /* Type of RHS table. IN_INDEX_* */
  int iTab = pParse->nTab++;            /* Cursor of the RHS table */
  int mustBeUnique;                     /* True if RHS must be unique */
  Vdbe *v = sqlite3GetVdbe(pParse);     /* Virtual machine being coded */

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      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }else if( prRhsHasNull ){
      *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
    }
    assert( pX->op==TK_IN );
    sqlite3CodeRhsOfIN(pParse, pX, eType==IN_INDEX_ROWID);
    if( rMayHaveNull ){
      sqlite3SetHasNullFlag(v, pX->iTable, rMayHaveNull);
    }
    pParse->nQueryLoop = savedNQueryLoop;
  }else{
    pX->iTable = iTab;
  }

  if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){
    int i, n;
    n = sqlite3ExprVectorSize(pX->pLeft);
    for(i=0; i<n; i++) aiMap[i] = i;
  }

  return eType;
}
#endif

#ifndef SQLITE_OMIT_SUBQUERY
/*
** Argument pExpr is an (?, ?...) IN(...) expression. This 







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      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }else if( prRhsHasNull ){
      *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
    }
    assert( pX->op==TK_IN );
    sqlite3CodeRhsOfIN(pParse, pX, iTab, eType==IN_INDEX_ROWID);
    if( rMayHaveNull ){
      sqlite3SetHasNullFlag(v, iTab, rMayHaveNull);
    }
    pParse->nQueryLoop = savedNQueryLoop;


  }

  if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){
    int i, n;
    n = sqlite3ExprVectorSize(pX->pLeft);
    for(i=0; i<n; i++) aiMap[i] = i;
  }
  *piTab = iTab;
  return eType;
}
#endif

#ifndef SQLITE_OMIT_SUBQUERY
/*
** Argument pExpr is an (?, ?...) IN(...) expression. This 
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** Generate code that will construct an ephemeral table containing all terms
** in the RHS of an IN operator.  The IN operator can be in either of two
** forms:
**
**     x IN (4,5,11)              -- IN operator with list on right-hand side
**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
**
** The pExpr parameter is the IN operator.




**
** If parameter isRowid is non-zero, then LHS of the IN operator is guaranteed
** to be a non-null integer. In this case, the ephemeral table can be an
** table B-Tree that keyed by only integers.  The more general cases uses
** an index B-Tree which can have arbitrary keys, but is slower to both
** read and write.
**
** If the LHS expression ("x" in the examples) is a column value, or
** the SELECT statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
void sqlite3CodeRhsOfIN(
  Parse *pParse,          /* Parsing context */
  Expr *pExpr,            /* The IN operator */

  int isRowid             /* If true, LHS is a rowid */
){
  int jmpIfDynamic = -1;      /* One-time test address */
  int addr;                   /* Address of OP_OpenEphemeral instruction */
  Expr *pLeft;                /* the LHS of the IN operator */
  KeyInfo *pKeyInfo = 0;      /* Key information */
  int nVal;                   /* Size of vector pLeft */
  Vdbe *v;                    /* The prepared statement under construction */

  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );

  /* The evaluation of the RHS of IN operator must be repeated every time it
  ** is encountered if any of the following is true:
  **
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){



















    jmpIfDynamic = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }

  /* Check to see if this is a vector IN operator */
  pLeft = pExpr->pLeft;
  nVal = sqlite3ExprVectorSize(pLeft);
  assert( !isRowid || nVal==1 );

  /* Construct the ephemeral table that will contain the content of
  ** RHS of the IN operator.
  */
  pExpr->iTable = pParse->nTab++;
  addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, 
      pExpr->iTable, (isRowid?0:nVal));







  pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 1);

  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    /* Case 1:     expr IN (SELECT ...)
    **
    ** Generate code to write the results of the select into the temporary
    ** table allocated and opened above.
    */
    Select *pSelect = pExpr->x.pSelect;
    ExprList *pEList = pSelect->pEList;

    ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY",
        jmpIfDynamic>=0?"":"CORRELATED "
    ));
    assert( !isRowid );
    /* If the LHS and RHS of the IN operator do not match, that
    ** error will have been caught long before we reach this point. */
    if( ALWAYS(pEList->nExpr==nVal) ){
      SelectDest dest;
      int i;







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** Generate code that will construct an ephemeral table containing all terms
** in the RHS of an IN operator.  The IN operator can be in either of two
** forms:
**
**     x IN (4,5,11)              -- IN operator with list on right-hand side
**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
**
** The pExpr parameter is the IN operator.  The cursor number for the
** constructed ephermeral table is returned.  The first time the ephemeral
** table is computed, the cursor number is also stored in pExpr->iTable,
** however the cursor number returned might not be the same, as it might
** have been duplicated using OP_OpenDup.
**
** If parameter isRowid is non-zero, then LHS of the IN operator is guaranteed
** to be a non-null integer. In this case, the ephemeral table can be an
** table B-Tree that keyed by only integers.  The more general cases uses
** an index B-Tree which can have arbitrary keys, but is slower to both
** read and write.
**
** If the LHS expression ("x" in the examples) is a column value, or
** the SELECT statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
void sqlite3CodeRhsOfIN(
  Parse *pParse,          /* Parsing context */
  Expr *pExpr,            /* The IN operator */
  int iTab,               /* Use this cursor number */
  int isRowid             /* If true, LHS is a rowid */
){
  int addrOnce = 0;           /* Address of the OP_Once instruction at top */
  int addr;                   /* Address of OP_OpenEphemeral instruction */
  Expr *pLeft;                /* the LHS of the IN operator */
  KeyInfo *pKeyInfo = 0;      /* Key information */
  int nVal;                   /* Size of vector pLeft */
  Vdbe *v;                    /* The prepared statement under construction */

  v = pParse->pVdbe;
  assert( v!=0 );

  /* The evaluation of the IN must be repeated every time it
  ** is encountered if any of the following is true:
  **
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can compute the RHS just once
  ** and reuse it many names.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    /* Reuse of the RHS is allowed */
    /* If this routine has already been coded, but the previous code
    ** might not have been invoked yet, so invoke it now as a subroutine. 
    */
    if( ExprHasProperty(pExpr, EP_Subrtn) ){
      sqlite3VdbeAddOp2(v, OP_Once, 0, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn,
                        pExpr->y.sub.iAddr);
      sqlite3VdbeAddOp2(v, OP_OpenDup, iTab, pExpr->iTable);
      return;
    }

    /* Begin coding the subroutine */
    ExprSetProperty(pExpr, EP_Subrtn);
    pExpr->y.sub.regReturn = ++pParse->nMem;
    pExpr->y.sub.iAddr =
      sqlite3VdbeAddOp2(v, OP_Integer, 0, pExpr->y.sub.regReturn) + 1;
    VdbeComment((v, "return address"));

    addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }

  /* Check to see if this is a vector IN operator */
  pLeft = pExpr->pLeft;
  nVal = sqlite3ExprVectorSize(pLeft);
  assert( !isRowid || nVal==1 );

  /* Construct the ephemeral table that will contain the content of
  ** RHS of the IN operator.
  */
  pExpr->iTable = iTab;
  addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, 
      pExpr->iTable, (isRowid?0:nVal));
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    VdbeComment((v, "Result of SELECT %u", pExpr->x.pSelect->selId));
  }else{
    VdbeComment((v, "RHS of IN operator"));
  }
#endif
  pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 1);

  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    /* Case 1:     expr IN (SELECT ...)
    **
    ** Generate code to write the results of the select into the temporary
    ** table allocated and opened above.
    */
    Select *pSelect = pExpr->x.pSelect;
    ExprList *pEList = pSelect->pEList;

    ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY %d",
        addrOnce?"":"CORRELATED ", pSelect->selId
    ));
    assert( !isRowid );
    /* If the LHS and RHS of the IN operator do not match, that
    ** error will have been caught long before we reach this point. */
    if( ALWAYS(pEList->nExpr==nVal) ){
      SelectDest dest;
      int i;
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      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( jmpIfDynamic>=0 && !sqlite3ExprIsConstant(pE2) ){
        sqlite3VdbeChangeToNoop(v, jmpIfDynamic);
        jmpIfDynamic = -1;
      }

      /* 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);







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      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( addrOnce && !sqlite3ExprIsConstant(pE2) ){
        sqlite3VdbeChangeToNoop(v, addrOnce);
        addrOnce = 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);
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    }
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
  if( pKeyInfo ){
    sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
  }
  if( jmpIfDynamic>=0 ){
    sqlite3VdbeJumpHere(v, jmpIfDynamic);



  }
}
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Generate code for scalar subqueries used as a subquery expression
** or EXISTS operator:
**
**     (SELECT a FROM b)          -- subquery
**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
**
** The pExpr parameter is the SELECT or EXISTS operator to be coded.
**
** The register that holds the result.  For a multi-column SELECT, 
** the result is stored in a contiguous array of registers and the
** return value is the register of the left-most result column.
** Return 0 if an error occurs.
*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
  int jmpIfDynamic = -1;      /* One-time test address */
  int rReg = 0;               /* Register storing resulting */
  Select *pSel;               /* SELECT statement to encode */
  SelectDest dest;            /* How to deal with SELECT result */
  int nReg;                   /* Registers to allocate */
  Expr *pLimit;               /* New limit expression */

  Vdbe *v = sqlite3GetVdbe(pParse);
  assert( v!=0 );














  /* The evaluation of the EXISTS/SELECT must be repeated every time it
  ** is encountered if any of the following is true:
  **
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    jmpIfDynamic = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }
  
  /* For a SELECT, generate code to put the values for all columns of
  ** the first row into an array of registers and return the index of
  ** the first register.
  **
  ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists)
  ** into a register and return that register number.
  **
  ** In both cases, the query is augmented with "LIMIT 1".  Any 
  ** preexisting limit is discarded in place of the new LIMIT 1.
  */
  testcase( pExpr->op==TK_EXISTS );
  testcase( pExpr->op==TK_SELECT );
  assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
  assert( ExprHasProperty(pExpr, EP_xIsSelect) );

  pSel = pExpr->x.pSelect;
  ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY",
        jmpIfDynamic>=0?"":"CORRELATED "));
  nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1;
  sqlite3SelectDestInit(&dest, 0, pParse->nMem+1);
  pParse->nMem += nReg;
  if( pExpr->op==TK_SELECT ){
    dest.eDest = SRT_Mem;
    dest.iSdst = dest.iSDParm;
    dest.nSdst = nReg;







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    }
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
  if( pKeyInfo ){
    sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
  }
  if( addrOnce ){
    sqlite3VdbeJumpHere(v, addrOnce);
    /* Subroutine return */
    sqlite3VdbeAddOp1(v, OP_Return, pExpr->y.sub.regReturn);
    sqlite3VdbeChangeP1(v, pExpr->y.sub.iAddr-1, sqlite3VdbeCurrentAddr(v)-1);
  }
}
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Generate code for scalar subqueries used as a subquery expression
** or EXISTS operator:
**
**     (SELECT a FROM b)          -- subquery
**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
**
** The pExpr parameter is the SELECT or EXISTS operator to be coded.
**
** The register that holds the result.  For a multi-column SELECT, 
** the result is stored in a contiguous array of registers and the
** return value is the register of the left-most result column.
** Return 0 if an error occurs.
*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
  int addrOnce = 0;           /* Address of OP_Once at top of subroutine */
  int rReg = 0;               /* Register storing resulting */
  Select *pSel;               /* SELECT statement to encode */
  SelectDest dest;            /* How to deal with SELECT result */
  int nReg;                   /* Registers to allocate */
  Expr *pLimit;               /* New limit expression */

  Vdbe *v = pParse->pVdbe;
  assert( v!=0 );

  /* If this routine has already been coded, then invoke it as a subroutine. */
  if( ExprHasProperty(pExpr, EP_Subrtn) ){
    sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn, pExpr->y.sub.iAddr);
    return pExpr->iTable;
  }

  /* Begin coding the subroutine */
  ExprSetProperty(pExpr, EP_Subrtn);
  pExpr->y.sub.regReturn = ++pParse->nMem;
  pExpr->y.sub.iAddr =
    sqlite3VdbeAddOp2(v, OP_Integer, 0, pExpr->y.sub.regReturn) + 1;
  VdbeComment((v, "return address"));

  /* The evaluation of the IN/EXISTS/SELECT must be repeated every time it
  ** is encountered if any of the following is true:
  **
  **    *  The right-hand side is a correlated subquery
  **    *  The right-hand side is an expression list containing variables
  **    *  We are inside a trigger
  **
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasProperty(pExpr, EP_VarSelect) ){
    addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }
  
  /* For a SELECT, generate code to put the values for all columns of
  ** the first row into an array of registers and return the index of
  ** the first register.
  **
  ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists)
  ** into a register and return that register number.
  **
  ** In both cases, the query is augmented with "LIMIT 1".  Any 
  ** preexisting limit is discarded in place of the new LIMIT 1.
  */
  testcase( pExpr->op==TK_EXISTS );
  testcase( pExpr->op==TK_SELECT );
  assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
  assert( ExprHasProperty(pExpr, EP_xIsSelect) );

  pSel = pExpr->x.pSelect;
  ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY",
        addrOnce?"":"CORRELATED "));
  nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1;
  sqlite3SelectDestInit(&dest, 0, pParse->nMem+1);
  pParse->nMem += nReg;
  if( pExpr->op==TK_SELECT ){
    dest.eDest = SRT_Mem;
    dest.iSdst = dest.iSDParm;
    dest.nSdst = nReg;
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896




2897
2898
2899
2900
2901
2902
2903
  }else{
    pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0);
  }
  pSel->iLimit = 0;
  if( sqlite3Select(pParse, pSel, &dest) ){
    return 0;
  }
  rReg = dest.iSDParm;
  ExprSetVVAProperty(pExpr, EP_NoReduce);

  if( jmpIfDynamic>=0 ){
    sqlite3VdbeJumpHere(v, jmpIfDynamic);
  }





  return rReg;
}
#endif /* SQLITE_OMIT_SUBQUERY */

#ifndef SQLITE_OMIT_SUBQUERY
/*
** Expr pIn is an IN(...) expression. This function checks that the 







|

|
<
|


>
>
>
>







2931
2932
2933
2934
2935
2936
2937
2938
2939
2940

2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
  }else{
    pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0);
  }
  pSel->iLimit = 0;
  if( sqlite3Select(pParse, pSel, &dest) ){
    return 0;
  }
  pExpr->iTable = rReg = dest.iSDParm;
  ExprSetVVAProperty(pExpr, EP_NoReduce);
  if( addrOnce ){

    sqlite3VdbeJumpHere(v, addrOnce);
  }

  /* Subroutine return */
  sqlite3VdbeAddOp1(v, OP_Return, pExpr->y.sub.regReturn);
  sqlite3VdbeChangeP1(v, pExpr->y.sub.iAddr-1, sqlite3VdbeCurrentAddr(v)-1);

  return rReg;
}
#endif /* SQLITE_OMIT_SUBQUERY */

#ifndef SQLITE_OMIT_SUBQUERY
/*
** Expr pIn is an IN(...) expression. This function checks that the 
2964
2965
2966
2967
2968
2969
2970

2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990

2991
2992
2993
2994
2995
2996
2997
  Expr *pLeft;          /* The LHS of the IN operator */
  int i;                /* loop counter */
  int destStep2;        /* Where to jump when NULLs seen in step 2 */
  int destStep6 = 0;    /* Start of code for Step 6 */
  int addrTruthOp;      /* Address of opcode that determines the IN is true */
  int destNotNull;      /* Jump here if a comparison is not true in step 6 */
  int addrTop;          /* Top of the step-6 loop */ 


  pLeft = pExpr->pLeft;
  if( sqlite3ExprCheckIN(pParse, pExpr) ) return;
  zAff = exprINAffinity(pParse, pExpr);
  nVector = sqlite3ExprVectorSize(pExpr->pLeft);
  aiMap = (int*)sqlite3DbMallocZero(
      pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1
  );
  if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error;

  /* Attempt to compute the RHS. After this step, if anything other than
  ** IN_INDEX_NOOP is returned, the table opened ith cursor pExpr->iTable 
  ** contains the values that make up the RHS. If IN_INDEX_NOOP is returned,
  ** the RHS has not yet been coded.  */
  v = pParse->pVdbe;
  assert( v!=0 );       /* OOM detected prior to this routine */
  VdbeNoopComment((v, "begin IN expr"));
  eType = sqlite3FindInIndex(pParse, pExpr,
                             IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK,
                             destIfFalse==destIfNull ? 0 : &rRhsHasNull, aiMap);


  assert( pParse->nErr || nVector==1 || eType==IN_INDEX_EPH
       || eType==IN_INDEX_INDEX_ASC || eType==IN_INDEX_INDEX_DESC 
  );
#ifdef SQLITE_DEBUG
  /* Confirm that aiMap[] contains nVector integer values between 0 and
  ** nVector-1. */







>











|







|
>







3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
  Expr *pLeft;          /* The LHS of the IN operator */
  int i;                /* loop counter */
  int destStep2;        /* Where to jump when NULLs seen in step 2 */
  int destStep6 = 0;    /* Start of code for Step 6 */
  int addrTruthOp;      /* Address of opcode that determines the IN is true */
  int destNotNull;      /* Jump here if a comparison is not true in step 6 */
  int addrTop;          /* Top of the step-6 loop */ 
  int iTab = 0;         /* Index to use */

  pLeft = pExpr->pLeft;
  if( sqlite3ExprCheckIN(pParse, pExpr) ) return;
  zAff = exprINAffinity(pParse, pExpr);
  nVector = sqlite3ExprVectorSize(pExpr->pLeft);
  aiMap = (int*)sqlite3DbMallocZero(
      pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1
  );
  if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error;

  /* Attempt to compute the RHS. After this step, if anything other than
  ** IN_INDEX_NOOP is returned, the table opened with cursor iTab
  ** contains the values that make up the RHS. If IN_INDEX_NOOP is returned,
  ** the RHS has not yet been coded.  */
  v = pParse->pVdbe;
  assert( v!=0 );       /* OOM detected prior to this routine */
  VdbeNoopComment((v, "begin IN expr"));
  eType = sqlite3FindInIndex(pParse, pExpr,
                             IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK,
                             destIfFalse==destIfNull ? 0 : &rRhsHasNull,
                             aiMap, &iTab);

  assert( pParse->nErr || nVector==1 || eType==IN_INDEX_EPH
       || eType==IN_INDEX_INDEX_ASC || eType==IN_INDEX_INDEX_DESC 
  );
#ifdef SQLITE_DEBUG
  /* Confirm that aiMap[] contains nVector integer values between 0 and
  ** nVector-1. */
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
  ** of the RHS using the LHS as a probe.  If found, the result is
  ** true.
  */
  if( eType==IN_INDEX_ROWID ){
    /* In this case, the RHS is the ROWID of table b-tree and so we also
    ** know that the RHS is non-NULL.  Hence, we combine steps 3 and 4
    ** into a single opcode. */
    sqlite3VdbeAddOp3(v, OP_SeekRowid, pExpr->iTable, destIfFalse, rLhs);
    VdbeCoverage(v);
    addrTruthOp = sqlite3VdbeAddOp0(v, OP_Goto);  /* Return True */
  }else{
    sqlite3VdbeAddOp4(v, OP_Affinity, rLhs, nVector, 0, zAff, nVector);
    if( destIfFalse==destIfNull ){
      /* Combine Step 3 and Step 5 into a single opcode */
      sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse,
                           rLhs, nVector); VdbeCoverage(v);
      goto sqlite3ExprCodeIN_finished;
    }
    /* Ordinary Step 3, for the case where FALSE and NULL are distinct */
    addrTruthOp = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0,
                                      rLhs, nVector); VdbeCoverage(v);
  }

  /* Step 4.  If the RHS is known to be non-NULL and we did not find
  ** an match on the search above, then the result must be FALSE.
  */
  if( rRhsHasNull && nVector==1 ){







|






|




|







3144
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3146
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3148
3149
3150
3151
3152
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3162
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3170
  ** of the RHS using the LHS as a probe.  If found, the result is
  ** true.
  */
  if( eType==IN_INDEX_ROWID ){
    /* In this case, the RHS is the ROWID of table b-tree and so we also
    ** know that the RHS is non-NULL.  Hence, we combine steps 3 and 4
    ** into a single opcode. */
    sqlite3VdbeAddOp3(v, OP_SeekRowid, iTab, destIfFalse, rLhs);
    VdbeCoverage(v);
    addrTruthOp = sqlite3VdbeAddOp0(v, OP_Goto);  /* Return True */
  }else{
    sqlite3VdbeAddOp4(v, OP_Affinity, rLhs, nVector, 0, zAff, nVector);
    if( destIfFalse==destIfNull ){
      /* Combine Step 3 and Step 5 into a single opcode */
      sqlite3VdbeAddOp4Int(v, OP_NotFound, iTab, destIfFalse,
                           rLhs, nVector); VdbeCoverage(v);
      goto sqlite3ExprCodeIN_finished;
    }
    /* Ordinary Step 3, for the case where FALSE and NULL are distinct */
    addrTruthOp = sqlite3VdbeAddOp4Int(v, OP_Found, iTab, 0,
                                      rLhs, nVector); VdbeCoverage(v);
  }

  /* Step 4.  If the RHS is known to be non-NULL and we did not find
  ** an match on the search above, then the result must be FALSE.
  */
  if( rRhsHasNull && nVector==1 ){
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
  ** If any comparison is NULL, then the result is NULL.  If all
  ** comparisons are FALSE then the final result is FALSE.
  **
  ** For a scalar LHS, it is sufficient to check just the first row
  ** of the RHS.
  */
  if( destStep6 ) sqlite3VdbeResolveLabel(v, destStep6);
  addrTop = sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
  VdbeCoverage(v);
  if( nVector>1 ){
    destNotNull = sqlite3VdbeMakeLabel(v);
  }else{
    /* For nVector==1, combine steps 6 and 7 by immediately returning
    ** FALSE if the first comparison is not NULL */
    destNotNull = destIfFalse;
  }
  for(i=0; i<nVector; i++){
    Expr *p;
    CollSeq *pColl;
    int r3 = sqlite3GetTempReg(pParse);
    p = sqlite3VectorFieldSubexpr(pLeft, i);
    pColl = sqlite3ExprCollSeq(pParse, p);
    sqlite3VdbeAddOp3(v, OP_Column, pExpr->iTable, i, r3);
    sqlite3VdbeAddOp4(v, OP_Ne, rLhs+i, destNotNull, r3,
                      (void*)pColl, P4_COLLSEQ);
    VdbeCoverage(v);
    sqlite3ReleaseTempReg(pParse, r3);
  }
  sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
  if( nVector>1 ){
    sqlite3VdbeResolveLabel(v, destNotNull);
    sqlite3VdbeAddOp2(v, OP_Next, pExpr->iTable, addrTop+1);
    VdbeCoverage(v);

    /* Step 7:  If we reach this point, we know that the result must
    ** be false. */
    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
  }








|














|








|







3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
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3208
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3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
  ** If any comparison is NULL, then the result is NULL.  If all
  ** comparisons are FALSE then the final result is FALSE.
  **
  ** For a scalar LHS, it is sufficient to check just the first row
  ** of the RHS.
  */
  if( destStep6 ) sqlite3VdbeResolveLabel(v, destStep6);
  addrTop = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, destIfFalse);
  VdbeCoverage(v);
  if( nVector>1 ){
    destNotNull = sqlite3VdbeMakeLabel(v);
  }else{
    /* For nVector==1, combine steps 6 and 7 by immediately returning
    ** FALSE if the first comparison is not NULL */
    destNotNull = destIfFalse;
  }
  for(i=0; i<nVector; i++){
    Expr *p;
    CollSeq *pColl;
    int r3 = sqlite3GetTempReg(pParse);
    p = sqlite3VectorFieldSubexpr(pLeft, i);
    pColl = sqlite3ExprCollSeq(pParse, p);
    sqlite3VdbeAddOp3(v, OP_Column, iTab, i, r3);
    sqlite3VdbeAddOp4(v, OP_Ne, rLhs+i, destNotNull, r3,
                      (void*)pColl, P4_COLLSEQ);
    VdbeCoverage(v);
    sqlite3ReleaseTempReg(pParse, r3);
  }
  sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
  if( nVector>1 ){
    sqlite3VdbeResolveLabel(v, destNotNull);
    sqlite3VdbeAddOp2(v, OP_Next, iTab, addrTop+1);
    VdbeCoverage(v);

    /* Step 7:  If we reach this point, we know that the result must
    ** be false. */
    sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
  }

Changes to src/sqliteInt.h.
2481
2482
2483
2484
2485
2486
2487




2488
2489
2490
2491
2492
2493
2494
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  union {
    Table *pTab;           /* TK_COLUMN: Table containing column. Can be NULL
                           ** for a column of an index on an expression */
    Window *pWin;          /* TK_FUNCTION: Window definition for the func */




  } y;
};

/*
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */







>
>
>
>







2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  union {
    Table *pTab;           /* TK_COLUMN: Table containing column. Can be NULL
                           ** for a column of an index on an expression */
    Window *pWin;          /* TK_FUNCTION: Window definition for the func */
    struct {               /* TK_IN, TK_SELECT, and TK_EXISTS */
      int iAddr;             /* Subroutine entry address */
      int regReturn;         /* Register used to hold return address */
    } sub;
  } y;
};

/*
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */
2512
2513
2514
2515
2516
2517
2518

2519
2520
2521
2522
2523
2524
2525
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
#define EP_Alias     0x400000 /* Is an alias for a result set column */
#define EP_Leaf      0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
#define EP_WinFunc  0x1000000 /* TK_FUNCTION with Expr.y.pWin set */


/*
** The EP_Propagate mask is a set of properties that automatically propagate
** upwards into parent nodes.
*/
#define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)








>







2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
#define EP_Alias     0x400000 /* Is an alias for a result set column */
#define EP_Leaf      0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
#define EP_WinFunc  0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
#define EP_Subrtn   0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */

/*
** The EP_Propagate mask is a set of properties that automatically propagate
** upwards into parent nodes.
*/
#define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)

4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterFunctions(void);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*, int);
void sqlite3CodeRhsOfIN(Parse*, Expr*, int);
int sqlite3CodeSubselect(Parse*, Expr*);
void sqlite3SelectPrep(Parse*, Select*, NameContext*);
void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
int sqlite3ResolveExprNames(NameContext*, Expr*);
int sqlite3ResolveExprListNames(NameContext*, ExprList*);
void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);







|







4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterFunctions(void);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*, int);
void sqlite3CodeRhsOfIN(Parse*, Expr*, int, int);
int sqlite3CodeSubselect(Parse*, Expr*);
void sqlite3SelectPrep(Parse*, Select*, NameContext*);
void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
int sqlite3ResolveExprNames(NameContext*, Expr*);
int sqlite3ResolveExprListNames(NameContext*, ExprList*);
void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
#define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
/*
** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
*/
#define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
#define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
#define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*);

int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
int sqlite3JournalSize(sqlite3_vfs *);
#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
 || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
  int sqlite3JournalCreate(sqlite3_file *);
#endif







|







4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
#define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
/*
** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
*/
#define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
#define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
#define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*, int*);

int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
int sqlite3JournalSize(sqlite3_vfs *);
#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
 || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
  int sqlite3JournalCreate(sqlite3_file *);
#endif
Changes to src/vdbe.c.
3606
3607
3608
3609
3610
3611
3612

3613
3614
3615
3616
3617
3618
3619
3620

  pCx = allocateCursor(p, pOp->p1, pOrig->nField, -1, CURTYPE_BTREE);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->isEphemeral = 1;
  pCx->pKeyInfo = pOrig->pKeyInfo;
  pCx->isTable = pOrig->isTable;

  rc = sqlite3BtreeCursor(pOrig->pBtx, MASTER_ROOT, BTREE_WRCSR,
                          pCx->pKeyInfo, pCx->uc.pCursor);
  /* The sqlite3BtreeCursor() routine can only fail for the first cursor
  ** opened for a database.  Since there is already an open cursor when this
  ** opcode is run, the sqlite3BtreeCursor() cannot fail */
  assert( rc==SQLITE_OK );
  break;
}







>
|







3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621

  pCx = allocateCursor(p, pOp->p1, pOrig->nField, -1, CURTYPE_BTREE);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->isEphemeral = 1;
  pCx->pKeyInfo = pOrig->pKeyInfo;
  pCx->isTable = pOrig->isTable;
  pCx->pgnoRoot = pOrig->pgnoRoot;
  rc = sqlite3BtreeCursor(pOrig->pBtx, pCx->pgnoRoot, BTREE_WRCSR,
                          pCx->pKeyInfo, pCx->uc.pCursor);
  /* The sqlite3BtreeCursor() routine can only fail for the first cursor
  ** opened for a database.  Since there is already an open cursor when this
  ** opcode is run, the sqlite3BtreeCursor() cannot fail */
  assert( rc==SQLITE_OK );
  break;
}
3678
3679
3680
3681
3682
3683
3684

3685
3686
3687
3688
3689
3690
3691
3692

3693
3694
3695
3696
3697
3698
3699
      int pgno;
      assert( pOp->p4type==P4_KEYINFO );
      rc = sqlite3BtreeCreateTable(pCx->pBtx, &pgno, BTREE_BLOBKEY | pOp->p5); 
      if( rc==SQLITE_OK ){
        assert( pgno==MASTER_ROOT+1 );
        assert( pKeyInfo->db==db );
        assert( pKeyInfo->enc==ENC(db) );

        rc = sqlite3BtreeCursor(pCx->pBtx, pgno, BTREE_WRCSR,
                                pKeyInfo, pCx->uc.pCursor);
      }
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBtx, MASTER_ROOT, BTREE_WRCSR,
                              0, pCx->uc.pCursor);
      pCx->isTable = 1;

    }
  }
  if( rc ) goto abort_due_to_error;
  pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
  break;
}








>








>







3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
      int pgno;
      assert( pOp->p4type==P4_KEYINFO );
      rc = sqlite3BtreeCreateTable(pCx->pBtx, &pgno, BTREE_BLOBKEY | pOp->p5); 
      if( rc==SQLITE_OK ){
        assert( pgno==MASTER_ROOT+1 );
        assert( pKeyInfo->db==db );
        assert( pKeyInfo->enc==ENC(db) );
        pCx->pgnoRoot = pgno;
        rc = sqlite3BtreeCursor(pCx->pBtx, pgno, BTREE_WRCSR,
                                pKeyInfo, pCx->uc.pCursor);
      }
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBtx, MASTER_ROOT, BTREE_WRCSR,
                              0, pCx->uc.pCursor);
      pCx->isTable = 1;
      pCx->pgnoRoot = MASTER_ROOT;
    }
  }
  if( rc ) goto abort_due_to_error;
  pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
  break;
}

Changes to src/where.c.
850
851
852
853
854
855
856

857
858
859
860
861
862
863
  if( pPartial ) sqlite3VdbeResolveLabel(v, iContinue);
  if( pTabItem->fg.viaCoroutine ){
    sqlite3VdbeChangeP2(v, addrCounter, regBase+n);
    testcase( pParse->db->mallocFailed );
    translateColumnToCopy(pParse, addrTop, pLevel->iTabCur,
                          pTabItem->regResult, 1);
    sqlite3VdbeGoto(v, addrTop);

  }else{
    sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1); VdbeCoverage(v);
  }
  sqlite3VdbeChangeP5(v, SQLITE_STMTSTATUS_AUTOINDEX);
  sqlite3VdbeJumpHere(v, addrTop);
  sqlite3ReleaseTempReg(pParse, regRecord);
  







>







850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
  if( pPartial ) sqlite3VdbeResolveLabel(v, iContinue);
  if( pTabItem->fg.viaCoroutine ){
    sqlite3VdbeChangeP2(v, addrCounter, regBase+n);
    testcase( pParse->db->mallocFailed );
    translateColumnToCopy(pParse, addrTop, pLevel->iTabCur,
                          pTabItem->regResult, 1);
    sqlite3VdbeGoto(v, addrTop);
    pTabItem->fg.viaCoroutine = 0;
  }else{
    sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1); VdbeCoverage(v);
  }
  sqlite3VdbeChangeP5(v, SQLITE_STMTSTATUS_AUTOINDEX);
  sqlite3VdbeJumpHere(v, addrTop);
  sqlite3ReleaseTempReg(pParse, regRecord);
  
Changes to src/wherecode.c.
534
535
536
537
538
539
540

541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
      }
    }
    for(i=iEq;i<pLoop->nLTerm; i++){
      assert( pLoop->aLTerm[i]!=0 );
      if( pLoop->aLTerm[i]->pExpr==pX ) nEq++;
    }


    if( (pX->flags & EP_xIsSelect)==0 || pX->x.pSelect->pEList->nExpr==1 ){
      eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, 0);
    }else{
      sqlite3 *db = pParse->db;
      pX = removeUnindexableInClauseTerms(pParse, iEq, pLoop, pX);

      if( !db->mallocFailed ){
        aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*nEq);
        eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap);
        pTerm->pExpr->iTable = pX->iTable;
      }
      sqlite3ExprDelete(db, pX);
      pX = pTerm->pExpr;
    }

    if( eType==IN_INDEX_INDEX_DESC ){
      testcase( bRev );
      bRev = !bRev;
    }
    iTab = pX->iTable;
    sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
    VdbeCoverageIf(v, bRev);
    VdbeCoverageIf(v, !bRev);
    assert( (pLoop->wsFlags & WHERE_MULTI_OR)==0 );

    pLoop->wsFlags |= WHERE_IN_ABLE;
    if( pLevel->u.in.nIn==0 ){







>

|






|
|









<







534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560

561
562
563
564
565
566
567
      }
    }
    for(i=iEq;i<pLoop->nLTerm; i++){
      assert( pLoop->aLTerm[i]!=0 );
      if( pLoop->aLTerm[i]->pExpr==pX ) nEq++;
    }

    iTab = 0;
    if( (pX->flags & EP_xIsSelect)==0 || pX->x.pSelect->pEList->nExpr==1 ){
      eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, 0, &iTab);
    }else{
      sqlite3 *db = pParse->db;
      pX = removeUnindexableInClauseTerms(pParse, iEq, pLoop, pX);

      if( !db->mallocFailed ){
        aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*nEq);
        eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap, &iTab);
        pTerm->pExpr->iTable = iTab;
      }
      sqlite3ExprDelete(db, pX);
      pX = pTerm->pExpr;
    }

    if( eType==IN_INDEX_INDEX_DESC ){
      testcase( bRev );
      bRev = !bRev;
    }

    sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
    VdbeCoverageIf(v, bRev);
    VdbeCoverageIf(v, !bRev);
    assert( (pLoop->wsFlags & WHERE_MULTI_OR)==0 );

    pLoop->wsFlags |= WHERE_IN_ABLE;
    if( pLevel->u.in.nIn==0 ){
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
    assert( (pTerm->prereqRight & pLevel->notReady)!=0 );
    pAlt = sqlite3WhereFindTerm(pWC, iCur, pTerm->u.leftColumn, notReady,
                    WO_EQ|WO_IN|WO_IS, 0);
    if( pAlt==0 ) continue;
    if( pAlt->wtFlags & (TERM_CODED) ) continue;
    if( (pAlt->eOperator & WO_IN) 
     && (pAlt->pExpr->flags & EP_xIsSelect)
     && (pAlt->pExpr->x.pSelect->pEList->nExpr>1)
    ){
      continue;
    }
    testcase( pAlt->eOperator & WO_EQ );
    testcase( pAlt->eOperator & WO_IS );
    testcase( pAlt->eOperator & WO_IN );
    VdbeModuleComment((v, "begin transitive constraint"));







|







2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
    assert( (pTerm->prereqRight & pLevel->notReady)!=0 );
    pAlt = sqlite3WhereFindTerm(pWC, iCur, pTerm->u.leftColumn, notReady,
                    WO_EQ|WO_IN|WO_IS, 0);
    if( pAlt==0 ) continue;
    if( pAlt->wtFlags & (TERM_CODED) ) continue;
    if( (pAlt->eOperator & WO_IN) 
     && (pAlt->pExpr->flags & EP_xIsSelect)
//     && (pAlt->pExpr->x.pSelect->pEList->nExpr>1)
    ){
      continue;
    }
    testcase( pAlt->eOperator & WO_EQ );
    testcase( pAlt->eOperator & WO_IS );
    testcase( pAlt->eOperator & WO_IN );
    VdbeModuleComment((v, "begin transitive constraint"));