/*
** pExpr points to an expression which implements a function.  If
** it is appropriate to apply the LIKE optimization to that function
** then set aWc[0] through aWc[2] to the wildcard characters and
** return TRUE.  If the function is not a LIKE-style function then
** return FALSE.





*/
int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
  FuncDef *pDef;
  if( pExpr->op!=TK_FUNCTION 
   || !pExpr->x.pList 
   || pExpr->x.pList->nExpr!=2
  ){

/*
** pExpr points to an expression which implements a function.  If
** it is appropriate to apply the LIKE optimization to that function
** then set aWc[0] through aWc[2] to the wildcard characters and
** return TRUE.  If the function is not a LIKE-style function then
** return FALSE.
**
** *pIsNocase is set to true if uppercase and lowercase are equivalent for
** the function (default for LIKE).  If the function makes the distinction
** between uppercase and lowercase (as does GLOB) then *pIsNocase is set to
** false.
*/
int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
  FuncDef *pDef;
  if( pExpr->op!=TK_FUNCTION 
   || !pExpr->x.pList 
   || pExpr->x.pList->nExpr!=2
  ){

  if( pSort->sortFlags & SORTFLAG_UseSorter ){
    op = OP_SorterInsert;
  }else{
    op = OP_IdxInsert;
  }
  sqlite3VdbeAddOp2(v, op, pSort->iECursor, regRecord);
  if( pSelect->iLimit ){
    int addr1, addr2;
    int iLimit;
    if( pSelect->iOffset ){
      iLimit = pSelect->iOffset+1;
    }else{
      iLimit = pSelect->iLimit;
    }
    addr1 = sqlite3VdbeAddOp1(v, OP_IfZero, iLimit); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_AddImm, iLimit, -1);
    addr2 = sqlite3VdbeAddOp0(v, OP_Goto);
    sqlite3VdbeJumpHere(v, addr1);
    sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor);
    sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor);
    sqlite3VdbeJumpHere(v, addr2);
  }
}

/*
** Add code to implement the OFFSET
*/
static void codeOffset(
................................................................................
  }

  /* Jump to the end of the loop if the LIMIT is reached.  Except, if
  ** there is a sorter, in which case the sorter has already limited
  ** the output for us.
  */
  if( pSort==0 && p->iLimit ){
    sqlite3VdbeAddOp3(v, OP_IfZero, p->iLimit, iBreak, -1); VdbeCoverage(v);
  }
}

/*
** Allocate a KeyInfo object sufficient for an index of N key columns and
** X extra columns.
*/
................................................................................
      }else if( n>=0 && p->nSelectRow>(u64)n ){
        p->nSelectRow = n;
      }
    }else{
      sqlite3ExprCode(pParse, p->pLimit, iLimit);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit); VdbeCoverage(v);
      VdbeComment((v, "LIMIT counter"));
      sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak); VdbeCoverage(v);
    }
    if( p->pOffset ){
      p->iOffset = iOffset = ++pParse->nMem;
      pParse->nMem++;   /* Allocate an extra register for limit+offset */
      sqlite3ExprCode(pParse, p->pOffset, iOffset);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); VdbeCoverage(v);
      VdbeComment((v, "OFFSET counter"));
................................................................................

  /* Output the single row in Current */
  addrCont = sqlite3VdbeMakeLabel(v);
  codeOffset(v, regOffset, addrCont);
  selectInnerLoop(pParse, p, p->pEList, iCurrent,
      0, 0, pDest, addrCont, addrBreak);
  if( regLimit ){
    sqlite3VdbeAddOp3(v, OP_IfZero, regLimit, addrBreak, -1);
    VdbeCoverage(v);
  }
  sqlite3VdbeResolveLabel(v, addrCont);

  /* Execute the recursive SELECT taking the single row in Current as
  ** the value for the recursive-table. Store the results in the Queue.
  */
................................................................................
      if( rc ){
        goto multi_select_end;
      }
      p->pPrior = 0;
      p->iLimit = pPrior->iLimit;
      p->iOffset = pPrior->iOffset;
      if( p->iLimit ){
        addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit); VdbeCoverage(v);
        VdbeComment((v, "Jump ahead if LIMIT reached"));
      }
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &dest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
................................................................................
      break;
    }
  }

  /* Jump to the end of the loop if the LIMIT is reached.
  */
  if( p->iLimit ){
    sqlite3VdbeAddOp3(v, OP_IfZero, p->iLimit, iBreak, -1); VdbeCoverage(v);
  }

  /* Generate the subroutine return
  */
  sqlite3VdbeResolveLabel(v, iContinue);
  sqlite3VdbeAddOp1(v, OP_Return, regReturn);

  if( pSort->sortFlags & SORTFLAG_UseSorter ){
    op = OP_SorterInsert;
  }else{
    op = OP_IdxInsert;
  }
  sqlite3VdbeAddOp2(v, op, pSort->iECursor, regRecord);
  if( pSelect->iLimit ){
    int addr;
    int iLimit;
    if( pSelect->iOffset ){
      iLimit = pSelect->iOffset+1;
    }else{
      iLimit = pSelect->iLimit;
    }
    addr = sqlite3VdbeAddOp3(v, OP_IfNotZero, iLimit, 0, -1); VdbeCoverage(v);



    sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor);
    sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor);
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Add code to implement the OFFSET
*/
static void codeOffset(
................................................................................
  }

  /* Jump to the end of the loop if the LIMIT is reached.  Except, if
  ** there is a sorter, in which case the sorter has already limited
  ** the output for us.
  */
  if( pSort==0 && p->iLimit ){
    sqlite3VdbeAddOp2(v, OP_DecrJumpZero, p->iLimit, iBreak); VdbeCoverage(v);
  }
}

/*
** Allocate a KeyInfo object sufficient for an index of N key columns and
** X extra columns.
*/
................................................................................
      }else if( n>=0 && p->nSelectRow>(u64)n ){
        p->nSelectRow = n;
      }
    }else{
      sqlite3ExprCode(pParse, p->pLimit, iLimit);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit); VdbeCoverage(v);
      VdbeComment((v, "LIMIT counter"));
      sqlite3VdbeAddOp2(v, OP_IfNot, iLimit, iBreak); VdbeCoverage(v);
    }
    if( p->pOffset ){
      p->iOffset = iOffset = ++pParse->nMem;
      pParse->nMem++;   /* Allocate an extra register for limit+offset */
      sqlite3ExprCode(pParse, p->pOffset, iOffset);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); VdbeCoverage(v);
      VdbeComment((v, "OFFSET counter"));
................................................................................

  /* Output the single row in Current */
  addrCont = sqlite3VdbeMakeLabel(v);
  codeOffset(v, regOffset, addrCont);
  selectInnerLoop(pParse, p, p->pEList, iCurrent,
      0, 0, pDest, addrCont, addrBreak);
  if( regLimit ){
    sqlite3VdbeAddOp2(v, OP_DecrJumpZero, regLimit, addrBreak);
    VdbeCoverage(v);
  }
  sqlite3VdbeResolveLabel(v, addrCont);

  /* Execute the recursive SELECT taking the single row in Current as
  ** the value for the recursive-table. Store the results in the Queue.
  */
................................................................................
      if( rc ){
        goto multi_select_end;
      }
      p->pPrior = 0;
      p->iLimit = pPrior->iLimit;
      p->iOffset = pPrior->iOffset;
      if( p->iLimit ){
        addr = sqlite3VdbeAddOp1(v, OP_IfNot, p->iLimit); VdbeCoverage(v);
        VdbeComment((v, "Jump ahead if LIMIT reached"));
      }
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &dest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
................................................................................
      break;
    }
  }

  /* Jump to the end of the loop if the LIMIT is reached.
  */
  if( p->iLimit ){
    sqlite3VdbeAddOp2(v, OP_DecrJumpZero, p->iLimit, iBreak); VdbeCoverage(v);
  }

  /* Generate the subroutine return
  */
  sqlite3VdbeResolveLabel(v, iContinue);
  sqlite3VdbeAddOp1(v, OP_Return, regReturn);

}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
** into a String before it is executed for the first time.  During
** this transformation, the length of string P4 is computed and stored
** as the P1 parameter.
*/
case OP_String8: {         /* same as TK_STRING, out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = sqlite3Strlen30(pOp->p4.z);
................................................................................
#endif
  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }
  /* Fall through to the next case, OP_String */
}
  
/* Opcode: String P1 P2 * P4 *
** Synopsis: r[P2]='P4' (len=P1)
**
** The string value P4 of length P1 (bytes) is stored in register P2.





*/
case OP_String: {          /* out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
  pOut->z = pOp->p4.z;
  pOut->n = pOp->p1;
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);







  break;
}

/* Opcode: Null P1 P2 P3 * *
** Synopsis:  r[P2..P3]=NULL
**
** Write a NULL into registers P2.  If P3 greater than P2, then also write
................................................................................
  break;
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */

/* Opcode: IfPos P1 P2 * * *
** Synopsis: if r[P1]>0 goto P2
**

** If the value of register P1 is 1 or greater, jump to P2.

**
** It is illegal to use this instruction on a register that does
** not contain an integer.  An assertion fault will result if you try.


*/
case OP_IfPos: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ){
     pc = pOp->p2 - 1;
................................................................................
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i<0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfZero P1 P2 P3 * *
** Synopsis: r[P1]+=P3, if r[P1]==0 goto P2
**
** The register P1 must contain an integer.  Add literal P3 to the
** value in register P1.  If the result is exactly 0, jump to P2. 

*/
case OP_IfZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );


  pIn1->u.i += pOp->p3;















  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( pIn1->u.i==0 ){
     pc = pOp->p2 - 1;
  }
  break;
}



















/* Opcode: AggStep * P2 P3 P4 P5
** Synopsis: accum=r[P3] step(r[P2@P5])
**
** Execute the step function for an aggregate.  The
** function has P5 arguments.   P4 is a pointer to the FuncDef
** structure that specifies the function.  Use register
** P3 as the accumulator.

}
#endif

/* Opcode: String8 * P2 * P4 *
** Synopsis: r[P2]='P4'
**
** P4 points to a nul terminated UTF-8 string. This opcode is transformed 
** into a String opcode before it is executed for the first time.  During
** this transformation, the length of string P4 is computed and stored
** as the P1 parameter.
*/
case OP_String8: {         /* same as TK_STRING, out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOp->opcode = OP_String;
  pOp->p1 = sqlite3Strlen30(pOp->p4.z);
................................................................................
#endif
  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }
  /* Fall through to the next case, OP_String */
}
  
/* Opcode: String P1 P2 P3 P4 P5
** Synopsis: r[P2]='P4' (len=P1)
**
** The string value P4 of length P1 (bytes) is stored in register P2.
**
** If P5!=0 and the content of register P3 is greater than zero, then
** the datatype of the register P2 is converted to BLOB.  The content is
** the same sequence of bytes, it is merely interpreted as a BLOB instead
** of a string, as if it had been CAST.
*/
case OP_String: {          /* out2-prerelease */
  assert( pOp->p4.z!=0 );
  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
  pOut->z = pOp->p4.z;
  pOut->n = pOp->p1;
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
  if( pOp->p5 ){
    assert( pOp->p3>0 );
    assert( pOp->p3<=(p->nMem-p->nCursor) );
    pIn3 = &aMem[pOp->p3];
    assert( pIn3->flags & MEM_Int );
    if( pIn3->u.i ) pOut->flags = MEM_Blob|MEM_Static|MEM_Term;
  }
  break;
}

/* Opcode: Null P1 P2 P3 * *
** Synopsis:  r[P2..P3]=NULL
**
** Write a NULL into registers P2.  If P3 greater than P2, then also write
................................................................................
  break;
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */

/* Opcode: IfPos P1 P2 * * *
** Synopsis: if r[P1]>0 goto P2
**
** Register P1 must contain an integer.
** If the value of register P1 is 1 or greater, jump to P2 and
** add the literal value P3 to register P1.
**


** If the initial value of register P1 is less than 1, then the
** value is unchanged and control passes through to the next instruction.
*/
case OP_IfPos: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ){
     pc = pOp->p2 - 1;
................................................................................
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i<0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: IfNotZero P1 P2 P3 * *
** Synopsis: if r[P1]!=0 then r[P1]+=P3, goto P2
**
** Register P1 must contain an integer.  If the content of register P1 is
** initially nonzero, then add P3 to P1 and jump to P2.  If register P1 is
** initially zero, leave it unchanged and fall through.
*/
case OP_IfNotZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i ){
     pIn1->u.i += pOp->p3;
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: DecrJumpZero P1 P2 * * *
** Synopsis: if (--r[P1])==0 goto P2
**
** Register P1 must hold an integer.  Decrement the value in register P1
** then jump to P2 if the new value is exactly zero.
*/
case OP_DecrJumpZero: {      /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  pIn1->u.i--;
  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( pIn1->u.i==0 ){
     pc = pOp->p2 - 1;
  }
  break;
}


/* Opcode: JumpZeroIncr P1 P2 * * *
** Synopsis: if (r[P1]++)==0 ) goto P2
**
** The register P1 must contain an integer.  If register P1 is initially
** zero, then jump to P2.  Increment register P1 regardless of whether or
** not the jump is taken.
*/
case OP_JumpZeroIncr: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( (pIn1->u.i++)==0 ){
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: AggStep * P2 P3 P4 P5
** Synopsis: accum=r[P3] step(r[P2@P5])
**
** Execute the step function for an aggregate.  The
** function has P5 arguments.   P4 is a pointer to the FuncDef
** structure that specifies the function.  Use register
** P3 as the accumulator.

** This is true even if this routine fails to allocate a new WhereTerm.
**
** WARNING:  This routine might reallocate the space used to store
** WhereTerms.  All pointers to WhereTerms should be invalidated after
** calling this routine.  Such pointers may be reinitialized by referencing
** the pWC->a[] array.
*/
static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
  WhereTerm *pTerm;
  int idx;
  testcase( wtFlags & TERM_VIRTUAL );
  if( pWC->nTerm>=pWC->nSlot ){
    WhereTerm *pOld = pWC->a;
    sqlite3 *db = pWC->pWInfo->pParse->db;
    pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
................................................................................
#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
/*
** Check to see if the given expression is a LIKE or GLOB operator that
** can be optimized using inequality constraints.  Return TRUE if it is
** so and false if not.
**
** In order for the operator to be optimizible, the RHS must be a string
** literal that does not begin with a wildcard.  




*/
static int isLikeOrGlob(
  Parse *pParse,    /* Parsing and code generating context */
  Expr *pExpr,      /* Test this expression */
  Expr **ppPrefix,  /* Pointer to TK_STRING expression with pattern prefix */
  int *pisComplete, /* True if the only wildcard is % in the last character */
  int *pnoCase      /* True if uppercase is equivalent to lowercase */
................................................................................
#ifdef SQLITE_EBCDIC
  if( *pnoCase ) return 0;
#endif
  pList = pExpr->x.pList;
  pLeft = pList->a[1].pExpr;
  if( pLeft->op!=TK_COLUMN 
   || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT 
   || IsVirtual(pLeft->pTab)
  ){
    /* IMP: R-02065-49465 The left-hand side of the LIKE or GLOB operator must
    ** be the name of an indexed column with TEXT affinity. */
    return 0;
  }
  assert( pLeft->iColumn!=(-1) ); /* Because IPK never has AFF_TEXT */

................................................................................
  WhereMaskSet *pMaskSet;          /* Set of table index masks */
  Expr *pExpr;                     /* The expression to be analyzed */
  Bitmask prereqLeft;              /* Prerequesites of the pExpr->pLeft */
  Bitmask prereqAll;               /* Prerequesites of pExpr */
  Bitmask extraRight = 0;          /* Extra dependencies on LEFT JOIN */
  Expr *pStr1 = 0;                 /* RHS of LIKE/GLOB operator */
  int isComplete = 0;              /* RHS of LIKE/GLOB ends with wildcard */
  int noCase = 0;                  /* LIKE/GLOB distinguishes case */
  int op;                          /* Top-level operator.  pExpr->op */
  Parse *pParse = pWInfo->pParse;  /* Parsing context */
  sqlite3 *db = pParse->db;        /* Database connection */

  if( db->mallocFailed ){
    return;
  }
................................................................................
  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
  /* Add constraints to reduce the search space on a LIKE or GLOB
  ** operator.
  **
  ** A like pattern of the form "x LIKE 'abc%'" is changed into constraints
  **
  **          x>='abc' AND x<'abd' AND x LIKE 'abc%'
  **
  ** The last character of the prefix "abc" is incremented to form the
  ** termination condition "abd".



  */
  if( pWC->op==TK_AND 
   && isLikeOrGlob(pParse, pExpr, &pStr1, &isComplete, &noCase)
  ){
    Expr *pLeft;       /* LHS of LIKE/GLOB operator */
    Expr *pStr2;       /* Copy of pStr1 - RHS of LIKE/GLOB operator */
    Expr *pNewExpr1;
    Expr *pNewExpr2;
    int idxNew1;
    int idxNew2;
    Token sCollSeqName;  /* Name of collating sequence */


    pLeft = pExpr->x.pList->a[1].pExpr;
    pStr2 = sqlite3ExprDup(db, pStr1, 0);















    if( !db->mallocFailed ){
      u8 c, *pC;       /* Last character before the first wildcard */
      pC = (u8*)&pStr2->u.zToken[sqlite3Strlen30(pStr2->u.zToken)-1];
      c = *pC;
      if( noCase ){
        /* The point is to increment the last character before the first
        ** wildcard.  But if we increment '@', that will push it into the
................................................................................
        c = sqlite3UpperToLower[c];
      }
      *pC = c + 1;
    }
    sCollSeqName.z = noCase ? "NOCASE" : "BINARY";
    sCollSeqName.n = 6;
    pNewExpr1 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, 
           sqlite3ExprAddCollateToken(pParse,pNewExpr1,&sCollSeqName),
           pStr1, 0);
    transferJoinMarkings(pNewExpr1, pExpr);
    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
    testcase( idxNew1==0 );
    exprAnalyze(pSrc, pWC, idxNew1);
    pNewExpr2 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
           sqlite3ExprAddCollateToken(pParse,pNewExpr2,&sCollSeqName),
           pStr2, 0);
    transferJoinMarkings(pNewExpr2, pExpr);
    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
    testcase( idxNew2==0 );
    exprAnalyze(pSrc, pWC, idxNew2);
    pTerm = &pWC->a[idxTerm];
    if( isComplete ){
      markTermAsChild(pWC, idxNew1, idxTerm);
      markTermAsChild(pWC, idxNew2, idxTerm);
    }
................................................................................
** Disabling a term causes that term to not be tested in the inner loop
** of the join.  Disabling is an optimization.  When terms are satisfied
** by indices, we disable them to prevent redundant tests in the inner
** loop.  We would get the correct results if nothing were ever disabled,
** but joins might run a little slower.  The trick is to disable as much
** as we can without disabling too much.  If we disabled in (1), we'd get
** the wrong answer.  See ticket #813.



















*/
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){

  if( pTerm
      && (pTerm->wtFlags & TERM_CODED)==0
      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
      && (pLevel->notReady & pTerm->prereqAll)==0
  ){
    pTerm->wtFlags |= TERM_CODED;
    if( pTerm->iParent>=0 ){
      WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
      if( (--pOther->nChild)==0 ){
        disableTerm(pLevel, pOther);
      }
    }



  }
}

/*
** Code an OP_Affinity opcode to apply the column affinity string zAff
** to the n registers starting at base. 
**
................................................................................
      v, addrExplain, pLvl->addrBody, pLvl->addrVisit, pLoop->nOut, zObj
  );
}
#else
# define addScanStatus(a, b, c, d) ((void)d)
#endif






















/*
** Generate code for the start of the iLevel-th loop in the WHERE clause
** implementation described by pWInfo.
*/
static Bitmask codeOneLoopStart(
  WhereInfo *pWInfo,   /* Complete information about the WHERE clause */
................................................................................
    if( pLoop->wsFlags & WHERE_BTM_LIMIT ){
      pRangeStart = pLoop->aLTerm[j++];
      nExtraReg = 1;
    }
    if( pLoop->wsFlags & WHERE_TOP_LIMIT ){
      pRangeEnd = pLoop->aLTerm[j++];
      nExtraReg = 1;













      if( pRangeStart==0
       && (j = pIdx->aiColumn[nEq])>=0 
       && pIdx->pTable->aCol[j].notNull==0
      ){
        bSeekPastNull = 1;
      }
    }
................................................................................
    start_constraints = pRangeStart || nEq>0;

    /* Seek the index cursor to the start of the range. */
    nConstraint = nEq;
    if( pRangeStart ){
      Expr *pRight = pRangeStart->pExpr->pRight;
      sqlite3ExprCode(pParse, pRight, regBase+nEq);

      if( (pRangeStart->wtFlags & TERM_VNULL)==0
       && sqlite3ExprCanBeNull(pRight)
      ){
        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
        VdbeCoverage(v);
      }
      if( zStartAff ){
................................................................................
    ** range (if any).
    */
    nConstraint = nEq;
    if( pRangeEnd ){
      Expr *pRight = pRangeEnd->pExpr->pRight;
      sqlite3ExprCacheRemove(pParse, regBase+nEq, 1);
      sqlite3ExprCode(pParse, pRight, regBase+nEq);

      if( (pRangeEnd->wtFlags & TERM_VNULL)==0
       && sqlite3ExprCanBeNull(pRight)
      ){
        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
        VdbeCoverage(v);
      }
      if( sqlite3CompareAffinity(pRight, cEndAff)!=SQLITE_AFF_NONE
................................................................................
#endif

  /* Insert code to test every subexpression that can be completely
  ** computed using the current set of tables.
  */
  for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
    Expr *pE;

    testcase( pTerm->wtFlags & TERM_VIRTUAL );
    testcase( pTerm->wtFlags & TERM_CODED );
    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
    if( (pTerm->prereqAll & pLevel->notReady)!=0 ){
      testcase( pWInfo->untestedTerms==0
               && (pWInfo->wctrlFlags & WHERE_ONETABLE_ONLY)!=0 );
      pWInfo->untestedTerms = 1;
      continue;
    }
    pE = pTerm->pExpr;
    assert( pE!=0 );
    if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
      continue;
    }





    sqlite3ExprIfFalse(pParse, pE, addrCont, SQLITE_JUMPIFNULL);

    pTerm->wtFlags |= TERM_CODED;
  }

  /* Insert code to test for implied constraints based on transitivity
  ** of the "==" operator.
  **
  ** Example: If the WHERE clause contains "t1.a=t2.b" and "t2.b=123"
................................................................................
    }
    sqlite3VdbeResolveLabel(v, pLevel->addrBrk);
    if( pLevel->addrSkip ){
      sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrSkip);
      VdbeComment((v, "next skip-scan on %s", pLoop->u.btree.pIndex->zName));
      sqlite3VdbeJumpHere(v, pLevel->addrSkip);
      sqlite3VdbeJumpHere(v, pLevel->addrSkip-2);










    }
    if( pLevel->iLeftJoin ){
      addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin); VdbeCoverage(v);
      assert( (pLoop->wsFlags & WHERE_IDX_ONLY)==0
           || (pLoop->wsFlags & WHERE_INDEXED)!=0 );
      if( (pLoop->wsFlags & WHERE_IDX_ONLY)==0 ){
        sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);

** This is true even if this routine fails to allocate a new WhereTerm.
**
** WARNING:  This routine might reallocate the space used to store
** WhereTerms.  All pointers to WhereTerms should be invalidated after
** calling this routine.  Such pointers may be reinitialized by referencing
** the pWC->a[] array.
*/
static int whereClauseInsert(WhereClause *pWC, Expr *p, u16 wtFlags){
  WhereTerm *pTerm;
  int idx;
  testcase( wtFlags & TERM_VIRTUAL );
  if( pWC->nTerm>=pWC->nSlot ){
    WhereTerm *pOld = pWC->a;
    sqlite3 *db = pWC->pWInfo->pParse->db;
    pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
................................................................................
#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
/*
** Check to see if the given expression is a LIKE or GLOB operator that
** can be optimized using inequality constraints.  Return TRUE if it is
** so and false if not.
**
** In order for the operator to be optimizible, the RHS must be a string
** literal that does not begin with a wildcard.  The LHS must be a column
** that may only be NULL, a string, or a BLOB, never a number. (This means
** that virtual tables cannot participate in the LIKE optimization.)  If the
** collating sequence for the column on the LHS must be appropriate for
** the operator.
*/
static int isLikeOrGlob(
  Parse *pParse,    /* Parsing and code generating context */
  Expr *pExpr,      /* Test this expression */
  Expr **ppPrefix,  /* Pointer to TK_STRING expression with pattern prefix */
  int *pisComplete, /* True if the only wildcard is % in the last character */
  int *pnoCase      /* True if uppercase is equivalent to lowercase */
................................................................................
#ifdef SQLITE_EBCDIC
  if( *pnoCase ) return 0;
#endif
  pList = pExpr->x.pList;
  pLeft = pList->a[1].pExpr;
  if( pLeft->op!=TK_COLUMN 
   || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT 
   || IsVirtual(pLeft->pTab)  /* Value might be numeric */
  ){
    /* IMP: R-02065-49465 The left-hand side of the LIKE or GLOB operator must
    ** be the name of an indexed column with TEXT affinity. */
    return 0;
  }
  assert( pLeft->iColumn!=(-1) ); /* Because IPK never has AFF_TEXT */

................................................................................
  WhereMaskSet *pMaskSet;          /* Set of table index masks */
  Expr *pExpr;                     /* The expression to be analyzed */
  Bitmask prereqLeft;              /* Prerequesites of the pExpr->pLeft */
  Bitmask prereqAll;               /* Prerequesites of pExpr */
  Bitmask extraRight = 0;          /* Extra dependencies on LEFT JOIN */
  Expr *pStr1 = 0;                 /* RHS of LIKE/GLOB operator */
  int isComplete = 0;              /* RHS of LIKE/GLOB ends with wildcard */
  int noCase = 0;                  /* uppercase equivalent to lowercase */
  int op;                          /* Top-level operator.  pExpr->op */
  Parse *pParse = pWInfo->pParse;  /* Parsing context */
  sqlite3 *db = pParse->db;        /* Database connection */

  if( db->mallocFailed ){
    return;
  }
................................................................................
  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
  /* Add constraints to reduce the search space on a LIKE or GLOB
  ** operator.
  **
  ** A like pattern of the form "x LIKE 'aBc%'" is changed into constraints
  **
  **          x>='ABC' AND x<'abd' AND x LIKE 'aBc%'
  **
  ** The last character of the prefix "abc" is incremented to form the
  ** termination condition "abd".  If case is not significant (the default
  ** for LIKE) then the lower-bound is made all uppercase and the upper-
  ** bound is made all lowercase so that the bounds also work when comparing
  ** BLOBs.
  */
  if( pWC->op==TK_AND 
   && isLikeOrGlob(pParse, pExpr, &pStr1, &isComplete, &noCase)
  ){
    Expr *pLeft;       /* LHS of LIKE/GLOB operator */
    Expr *pStr2;       /* Copy of pStr1 - RHS of LIKE/GLOB operator */
    Expr *pNewExpr1;
    Expr *pNewExpr2;
    int idxNew1;
    int idxNew2;
    Token sCollSeqName;  /* Name of collating sequence */
    const u16 wtFlags = TERM_LIKEOPT | TERM_VIRTUAL | TERM_DYNAMIC;

    pLeft = pExpr->x.pList->a[1].pExpr;
    pStr2 = sqlite3ExprDup(db, pStr1, 0);

    /* Convert the lower bound to upper-case and the upper bound to
    ** lower-case (upper-case is less than lower-case in ASCII) so that
    ** the range constraints also work for BLOBs
    */
    if( noCase && !pParse->db->mallocFailed ){
      int i;
      char c;
      pTerm->wtFlags |= TERM_LIKE;
      for(i=0; (c = pStr1->u.zToken[i])!=0; i++){
        pStr1->u.zToken[i] = sqlite3Toupper(c);
        pStr2->u.zToken[i] = sqlite3Tolower(c);
      }
    }

    if( !db->mallocFailed ){
      u8 c, *pC;       /* Last character before the first wildcard */
      pC = (u8*)&pStr2->u.zToken[sqlite3Strlen30(pStr2->u.zToken)-1];
      c = *pC;
      if( noCase ){
        /* The point is to increment the last character before the first
        ** wildcard.  But if we increment '@', that will push it into the
................................................................................
        c = sqlite3UpperToLower[c];
      }
      *pC = c + 1;
    }
    sCollSeqName.z = noCase ? "NOCASE" : "BINARY";
    sCollSeqName.n = 6;
    pNewExpr1 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr1 = sqlite3PExpr(pParse, TK_GE,
           sqlite3ExprAddCollateToken(pParse,pNewExpr1,&sCollSeqName),
           pStr1, 0);
    transferJoinMarkings(pNewExpr1, pExpr);
    idxNew1 = whereClauseInsert(pWC, pNewExpr1, wtFlags);
    testcase( idxNew1==0 );
    exprAnalyze(pSrc, pWC, idxNew1);
    pNewExpr2 = sqlite3ExprDup(db, pLeft, 0);
    pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
           sqlite3ExprAddCollateToken(pParse,pNewExpr2,&sCollSeqName),
           pStr2, 0);
    transferJoinMarkings(pNewExpr2, pExpr);
    idxNew2 = whereClauseInsert(pWC, pNewExpr2, wtFlags);
    testcase( idxNew2==0 );
    exprAnalyze(pSrc, pWC, idxNew2);
    pTerm = &pWC->a[idxTerm];
    if( isComplete ){
      markTermAsChild(pWC, idxNew1, idxTerm);
      markTermAsChild(pWC, idxNew2, idxTerm);
    }
................................................................................
** Disabling a term causes that term to not be tested in the inner loop
** of the join.  Disabling is an optimization.  When terms are satisfied
** by indices, we disable them to prevent redundant tests in the inner
** loop.  We would get the correct results if nothing were ever disabled,
** but joins might run a little slower.  The trick is to disable as much
** as we can without disabling too much.  If we disabled in (1), we'd get
** the wrong answer.  See ticket #813.
**
** If all the children of a term are disabled, then that term is also
** automatically disabled.  In this way, terms get disabled if derived
** virtual terms are tested first.  For example:
**
**      x GLOB 'abc*' AND x>='abc' AND x<'acd'
**      \___________/     \______/     \_____/
**         parent          child1       child2
**
** Only the parent term was in the original WHERE clause.  The child1
** and child2 terms were added by the LIKE optimization.  If both of
** the virtual child terms are valid, then testing of the parent can be 
** skipped.
**
** Usually the parent term is marked as TERM_CODED.  But if the parent
** term was originally TERM_LIKE, then the parent gets TERM_LIKECOND instead.
** The TERM_LIKECOND marking indicates that the term should be coded inside
** a conditional such that is only evaluated on the second pass of a
** LIKE-optimization loop, when scanning BLOBs instead of strings.
*/
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
  int nLoop = 0;
  while( pTerm
      && (pTerm->wtFlags & TERM_CODED)==0
      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
      && (pLevel->notReady & pTerm->prereqAll)==0
  ){
    if( nLoop && (pTerm->wtFlags & TERM_LIKE)!=0 ){
      pTerm->wtFlags |= TERM_LIKECOND;
    }else{
      pTerm->wtFlags |= TERM_CODED;
    }
    if( pTerm->iParent<0 ) break;
    pTerm = &pTerm->pWC->a[pTerm->iParent];
    pTerm->nChild--;
    if( pTerm->nChild!=0 ) break;
    nLoop++;
  }
}

/*
** Code an OP_Affinity opcode to apply the column affinity string zAff
** to the n registers starting at base. 
**
................................................................................
      v, addrExplain, pLvl->addrBody, pLvl->addrVisit, pLoop->nOut, zObj
  );
}
#else
# define addScanStatus(a, b, c, d) ((void)d)
#endif

/*
** Look at the last instruction coded.  If that instruction is OP_String8
** and if pLoop->iLikeRepCntr is non-zero, then change the P3 to be
** pLoop->iLikeRepCntr and set P5.
**
** The LIKE optimization trys to evaluate "x LIKE 'abc%'" as a range
** expression: "x>='ABC' AND x<'abd'".  But this requires that the range
** scan loop run twice, once for strings and a second time for BLOBs.
** The OP_String opcodes on the second pass convert the upper and lower
** bound string contants to blobs.  This routine makes the necessary changes
** to the OP_String opcodes for that to happen.
*/
static void whereLikeOptimizationStringFixup(Vdbe *v, WhereLevel *pLevel){
  VdbeOp *pOp;
  pOp = sqlite3VdbeGetOp(v, -1);
  if( pLevel->iLikeRepCntr && pOp->opcode==OP_String8 ){
    pOp->p3 = pLevel->iLikeRepCntr;
    pOp->p5 = 1;
  }
}

/*
** Generate code for the start of the iLevel-th loop in the WHERE clause
** implementation described by pWInfo.
*/
static Bitmask codeOneLoopStart(
  WhereInfo *pWInfo,   /* Complete information about the WHERE clause */
................................................................................
    if( pLoop->wsFlags & WHERE_BTM_LIMIT ){
      pRangeStart = pLoop->aLTerm[j++];
      nExtraReg = 1;
    }
    if( pLoop->wsFlags & WHERE_TOP_LIMIT ){
      pRangeEnd = pLoop->aLTerm[j++];
      nExtraReg = 1;
      if( pRangeStart
       && (pRangeStart->wtFlags & TERM_LIKEOPT)!=0
       && (pRangeEnd->wtFlags & TERM_LIKEOPT)!=0
      ){
        pLevel->iLikeRepCntr = ++pParse->nMem;
        testcase( bRev );
        testcase( pIdx->aSortOrder[nEq]==SQLITE_SO_DESC );
        sqlite3VdbeAddOp2(v, OP_Integer,
                          bRev ^ (pIdx->aSortOrder[nEq]==SQLITE_SO_DESC),
                          pLevel->iLikeRepCntr);
        VdbeComment((v, "LIKE loop counter"));
        pLevel->addrLikeRep = sqlite3VdbeCurrentAddr(v);
      }
      if( pRangeStart==0
       && (j = pIdx->aiColumn[nEq])>=0 
       && pIdx->pTable->aCol[j].notNull==0
      ){
        bSeekPastNull = 1;
      }
    }
................................................................................
    start_constraints = pRangeStart || nEq>0;

    /* Seek the index cursor to the start of the range. */
    nConstraint = nEq;
    if( pRangeStart ){
      Expr *pRight = pRangeStart->pExpr->pRight;
      sqlite3ExprCode(pParse, pRight, regBase+nEq);
      whereLikeOptimizationStringFixup(v, pLevel);
      if( (pRangeStart->wtFlags & TERM_VNULL)==0
       && sqlite3ExprCanBeNull(pRight)
      ){
        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
        VdbeCoverage(v);
      }
      if( zStartAff ){
................................................................................
    ** range (if any).
    */
    nConstraint = nEq;
    if( pRangeEnd ){
      Expr *pRight = pRangeEnd->pExpr->pRight;
      sqlite3ExprCacheRemove(pParse, regBase+nEq, 1);
      sqlite3ExprCode(pParse, pRight, regBase+nEq);
      whereLikeOptimizationStringFixup(v, pLevel);
      if( (pRangeEnd->wtFlags & TERM_VNULL)==0
       && sqlite3ExprCanBeNull(pRight)
      ){
        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
        VdbeCoverage(v);
      }
      if( sqlite3CompareAffinity(pRight, cEndAff)!=SQLITE_AFF_NONE
................................................................................
#endif

  /* Insert code to test every subexpression that can be completely
  ** computed using the current set of tables.
  */
  for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
    Expr *pE;
    int skipLikeAddr = 0;
    testcase( pTerm->wtFlags & TERM_VIRTUAL );
    testcase( pTerm->wtFlags & TERM_CODED );
    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
    if( (pTerm->prereqAll & pLevel->notReady)!=0 ){
      testcase( pWInfo->untestedTerms==0
               && (pWInfo->wctrlFlags & WHERE_ONETABLE_ONLY)!=0 );
      pWInfo->untestedTerms = 1;
      continue;
    }
    pE = pTerm->pExpr;
    assert( pE!=0 );
    if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
      continue;
    }
    if( pTerm->wtFlags & TERM_LIKECOND ){
      assert( pLevel->iLikeRepCntr>0 );
      skipLikeAddr = sqlite3VdbeAddOp1(v, OP_IfNot, pLevel->iLikeRepCntr);
      VdbeCoverage(v);
    }
    sqlite3ExprIfFalse(pParse, pE, addrCont, SQLITE_JUMPIFNULL);
    if( skipLikeAddr ) sqlite3VdbeJumpHere(v, skipLikeAddr);
    pTerm->wtFlags |= TERM_CODED;
  }

  /* Insert code to test for implied constraints based on transitivity
  ** of the "==" operator.
  **
  ** Example: If the WHERE clause contains "t1.a=t2.b" and "t2.b=123"
................................................................................
    }
    sqlite3VdbeResolveLabel(v, pLevel->addrBrk);
    if( pLevel->addrSkip ){
      sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrSkip);
      VdbeComment((v, "next skip-scan on %s", pLoop->u.btree.pIndex->zName));
      sqlite3VdbeJumpHere(v, pLevel->addrSkip);
      sqlite3VdbeJumpHere(v, pLevel->addrSkip-2);
    }
    if( pLevel->addrLikeRep ){
      int op;
      if( sqlite3VdbeGetOp(v, pLevel->addrLikeRep-1)->p1 ){
        op = OP_DecrJumpZero;
      }else{
        op = OP_JumpZeroIncr;
      }
      sqlite3VdbeAddOp2(v, op, pLevel->iLikeRepCntr, pLevel->addrLikeRep);
      VdbeCoverage(v);
    }
    if( pLevel->iLeftJoin ){
      addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin); VdbeCoverage(v);
      assert( (pLoop->wsFlags & WHERE_IDX_ONLY)==0
           || (pLoop->wsFlags & WHERE_INDEXED)!=0 );
      if( (pLoop->wsFlags & WHERE_IDX_ONLY)==0 ){
        sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);

  int iIdxCur;          /* The VDBE cursor used to access pIdx */
  int addrBrk;          /* Jump here to break out of the loop */
  int addrNxt;          /* Jump here to start the next IN combination */
  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, 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 {
................................................................................
  union {
    int leftColumn;         /* Column number of X in "X <op> <expr>" */
    WhereOrInfo *pOrInfo;   /* Extra information if (eOperator & WO_OR)!=0 */
    WhereAndInfo *pAndInfo; /* Extra information if (eOperator& WO_AND)!=0 */
  } u;
  LogEst truthProb;       /* Probability of truth for this expression */
  u16 eOperator;          /* A WO_xx value describing <op> */
  u8 wtFlags;             /* TERM_xxx bit flags.  See below */
  u8 nChild;              /* Number of children that must disable us */
  WhereClause *pWC;       /* The clause this term is part of */
  Bitmask prereqRight;    /* Bitmask of tables used by pExpr->pRight */
  Bitmask prereqAll;      /* Bitmask of tables referenced by pExpr */
};

/*
................................................................................
#define TERM_ANDINFO    0x20   /* Need to free the WhereTerm.u.pAndInfo obj */
#define TERM_OR_OK      0x40   /* Used during OR-clause processing */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
#  define TERM_VNULL    0x80   /* Manufactured x>NULL or x<=NULL term */
#else
#  define TERM_VNULL    0x00   /* Disabled if not using stat3 */
#endif




/*
** An instance of the WhereScan object is used as an iterator for locating
** terms in the WHERE clause that are useful to the query planner.
*/
struct WhereScan {
  WhereClause *pOrigWC;      /* Original, innermost WhereClause */

  int iIdxCur;          /* The VDBE cursor used to access pIdx */
  int addrBrk;          /* Jump here to break out of the loop */
  int addrNxt;          /* Jump here to start the next IN combination */
  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 */
  int iLikeRepCntr;     /* LIKE range processing counter register */
  int addrLikeRep;      /* LIKE range processing address */
  u8 iFrom;             /* Which entry in the FROM clause */
  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 {
................................................................................
  union {
    int leftColumn;         /* Column number of X in "X <op> <expr>" */
    WhereOrInfo *pOrInfo;   /* Extra information if (eOperator & WO_OR)!=0 */
    WhereAndInfo *pAndInfo; /* Extra information if (eOperator& WO_AND)!=0 */
  } u;
  LogEst truthProb;       /* Probability of truth for this expression */
  u16 eOperator;          /* A WO_xx value describing <op> */
  u16 wtFlags;            /* TERM_xxx bit flags.  See below */
  u8 nChild;              /* Number of children that must disable us */
  WhereClause *pWC;       /* The clause this term is part of */
  Bitmask prereqRight;    /* Bitmask of tables used by pExpr->pRight */
  Bitmask prereqAll;      /* Bitmask of tables referenced by pExpr */
};

/*
................................................................................
#define TERM_ANDINFO    0x20   /* Need to free the WhereTerm.u.pAndInfo obj */
#define TERM_OR_OK      0x40   /* Used during OR-clause processing */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
#  define TERM_VNULL    0x80   /* Manufactured x>NULL or x<=NULL term */
#else
#  define TERM_VNULL    0x00   /* Disabled if not using stat3 */
#endif
#define TERM_LIKEOPT    0x100  /* Virtual terms from the LIKE optimization */
#define TERM_LIKECOND   0x200  /* Conditionally this LIKE operator term */
#define TERM_LIKE       0x400  /* The original LIKE operator */

/*
** An instance of the WhereScan object is used as an iterator for locating
** terms in the WHERE clause that are useful to the query planner.
*/
struct WhereScan {
  WhereClause *pOrigWC;      /* Original, innermost WhereClause */

} {0 0 0 {SEARCH TABLE t1 USING INDEX i1 (b>? AND b<?)}}
do_eqp_test analyze3-2.3 {
  SELECT count(a) FROM t1 WHERE b LIKE '%a'
} {0 0 0 {SCAN TABLE t1}}

do_test analyze3-2.4 {
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE 'a%' }
} {101 0 100}
do_test analyze3-2.5 {
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE '%a' }
} {999 999 100}

do_test analyze3-2.4 {
  set like "a%"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {101 0 100}
do_test analyze3-2.5 {
  set like "%a"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {999 999 100}
do_test analyze3-2.6 {
  set like "a"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {101 0 0}
do_test analyze3-2.7 {
  set like "ab"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {11 0 0}
do_test analyze3-2.8 {
  set like "abc"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {2 0 1}
do_test analyze3-2.9 {
  set like "a_c"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {101 0 10}


#-------------------------------------------------------------------------
# This block of tests checks that statements are correctly marked as
# expired when the values bound to any parameters that may affect the 
# query plan are modified.
#

} {0 0 0 {SEARCH TABLE t1 USING INDEX i1 (b>? AND b<?)}}
do_eqp_test analyze3-2.3 {
  SELECT count(a) FROM t1 WHERE b LIKE '%a'
} {0 0 0 {SCAN TABLE t1}}

do_test analyze3-2.4 {
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE 'a%' }
} {102 0 100}
do_test analyze3-2.5 {
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE '%a' }
} {999 999 100}

do_test analyze3-2.6 {
  set like "a%"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {102 0 100}
do_test analyze3-2.7 {
  set like "%a"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {999 999 100}
do_test analyze3-2.8 {
  set like "a"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {102 0 0}
do_test analyze3-2.9 {
  set like "ab"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {12 0 0}
do_test analyze3-2.10 {
  set like "abc"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {3 0 1}
do_test analyze3-2.11 {
  set like "a_c"
  sf_execsql { SELECT count(*) FROM t1 WHERE b LIKE $like }
} {102 0 10}


#-------------------------------------------------------------------------
# This block of tests checks that statements are correctly marked as
# expired when the values bound to any parameters that may affect the 
# query plan are modified.
#

      SELECT a FROM t10 WHERE e LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.5 {
    count {
      SELECT a FROM t10 WHERE f LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 3 like 0}
  do_test like-10.6 {
    count {
      SELECT a FROM t10 WHERE a LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.10 {
    execsql {
................................................................................
      SELECT a FROM t10b WHERE e GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.14 {
    count {
      SELECT a FROM t10b WHERE f GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 3 like 0}
  do_test like-10.15 {
    count {
      SELECT a FROM t10b WHERE a GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
}

      SELECT a FROM t10 WHERE e LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.5 {
    count {
      SELECT a FROM t10 WHERE f LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 4 like 0}
  do_test like-10.6 {
    count {
      SELECT a FROM t10 WHERE a LIKE '12%' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.10 {
    execsql {
................................................................................
      SELECT a FROM t10b WHERE e GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
  do_test like-10.14 {
    count {
      SELECT a FROM t10b WHERE f GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 4 like 0}
  do_test like-10.15 {
    count {
      SELECT a FROM t10b WHERE a GLOB '12*' ORDER BY +a;
    }
  } {12 123 scan 5 like 6}
}

# 2015-03-06
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the LIKE and GLOB operators and
# in particular the optimizations that occur to help those operators
# run faster and that those optimizations work correctly when there
# are both strings and blobs being tested.
#
# Ticket 05f43be8fdda9fbd948d374319b99b054140bc36 shows that the following
# SQL was not working correctly:
#
#     CREATE TABLE t1(x TEXT UNIQUE COLLATE nocase);
#     INSERT INTO t1(x) VALUES(x'616263');
#     SELECT 'query-1', x FROM t1 WHERE x LIKE 'a%';
#     SELECT 'query-2', x FROM t1 WHERE +x LIKE 'a%';
#
# This script verifies that it works right now.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_execsql_test like3-1.1 {
  PRAGMA encoding=UTF8;
  CREATE TABLE t1(a,b TEXT COLLATE nocase);
  INSERT INTO t1(a,b)
     VALUES(1,'abc'),
           (2,'ABX'),
           (3,'BCD'),
           (4,x'616263'),
           (5,x'414258'),
           (6,x'424344');
  CREATE INDEX t1ba ON t1(b,a);

  SELECT a, b FROM t1 WHERE b LIKE 'aB%' ORDER BY +a;
} {1 abc 2 ABX 4 abc 5 ABX}
do_execsql_test like3-1.2 {
  SELECT a, b FROM t1 WHERE +b LIKE 'aB%' ORDER BY +a;
} {1 abc 2 ABX 4 abc 5 ABX}

do_execsql_test like3-2.0 {
  CREATE TABLE t2(a, b TEXT);
  INSERT INTO t2 SELECT a, b FROM t1;
  CREATE INDEX t2ba ON t2(b,a);
  SELECT a, b FROM t2 WHERE b GLOB 'ab*' ORDER BY +a;
} {1 abc 4 abc}
do_execsql_test like3-2.1 {
  SELECT a, b FROM t2 WHERE +b GLOB 'ab*' ORDER BY +a;
} {1 abc 4 abc}
do_execsql_test like3-2.2 {
  SELECT a, b FROM t2 WHERE b>=x'6162' AND b GLOB 'ab*'
} {4 abc}
do_execsql_test like3-2.3 {
  SELECT a, b FROM t2 WHERE +b>=x'6162' AND +b GLOB 'ab*'
} {4 abc}
do_execsql_test like3-2.4 {
  SELECT a, b FROM t2 WHERE b GLOB 'ab*' AND b>=x'6162'
} {4 abc}
do_execsql_test like3-2.5 {
  SELECT a, b FROM t2 WHERE +b GLOB 'ab*' AND +b>=x'6162'
} {4 abc}

do_execsql_test like3-3.0 {
  CREATE TABLE t3(x TEXT PRIMARY KEY COLLATE nocase);
  INSERT INTO t3(x) VALUES('aaa'),('abc'),('abd'),('abe'),('acz');
  INSERT INTO t3(x) SELECT CAST(x AS blob) FROM t3;
  SELECT quote(x) FROM t3 WHERE x LIKE 'ab%' ORDER BY x;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}
do_execsql_test like3-3.1 {
  SELECT quote(x) FROM t3 WHERE x LIKE 'ab%' ORDER BY x DESC;
} {X'616265' X'616264' X'616263' 'abe' 'abd' 'abc'}
do_execsql_test like3-3.1ck {
  SELECT quote(x) FROM t3 WHERE x LIKE 'ab%' ORDER BY +x DESC;
} {X'616265' X'616264' X'616263' 'abe' 'abd' 'abc'}
do_execsql_test like3-3.2 {
  SELECT quote(x) FROM t3 WHERE x LIKE 'ab%' ORDER BY x ASC;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}
do_execsql_test like3-3.2ck {
  SELECT quote(x) FROM t3 WHERE x LIKE 'ab%' ORDER BY +x ASC;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}

do_execsql_test like3-4.0 {
  CREATE TABLE t4(x TEXT COLLATE nocase);
  CREATE INDEX t4x ON t4(x DESC);
  INSERT INTO t4(x) SELECT x FROM t3;
  SELECT quote(x) FROM t4 WHERE x LIKE 'ab%' ORDER BY x;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}
do_execsql_test like3-4.1 {
  SELECT quote(x) FROM t4 WHERE x LIKE 'ab%' ORDER BY x DESC;
} {X'616265' X'616264' X'616263' 'abe' 'abd' 'abc'}
do_execsql_test like3-4.1ck {
  SELECT quote(x) FROM t4 WHERE x LIKE 'ab%' ORDER BY +x DESC;
} {X'616265' X'616264' X'616263' 'abe' 'abd' 'abc'}
do_execsql_test like3-4.2 {
  SELECT quote(x) FROM t4 WHERE x LIKE 'ab%' ORDER BY x ASC;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}
do_execsql_test like3-4.2ck {
  SELECT quote(x) FROM t4 WHERE x LIKE 'ab%' ORDER BY +x ASC;
} {'abc' 'abd' 'abe' X'616263' X'616264' X'616265'}



finish_test

do_test where8-1.3 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b = 'two' }
} {IX X II 0 0 6}

do_test where8-1.4 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b GLOB 't*' }
} {IX X III II 0 0 9}

do_test where8-1.5 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b GLOB 'f*' }
} {IX X V IV 0 0 9}

do_test where8-1.6 { 
  execsql_status { SELECT c FROM t1 WHERE a = 1 OR b = 'three' ORDER BY rowid }
} {I III 0 1}

do_test where8-1.7 { 
  execsql_status { SELECT c FROM t1 WHERE a = 1 OR b = 'three' ORDER BY a }

do_test where8-1.3 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b = 'two' }
} {IX X II 0 0 6}

do_test where8-1.4 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b GLOB 't*' }
} {IX X III II 0 0 10}

do_test where8-1.5 { 
  execsql_status2 { SELECT c FROM t1 WHERE a > 8 OR b GLOB 'f*' }
} {IX X V IV 0 0 10}

do_test where8-1.6 { 
  execsql_status { SELECT c FROM t1 WHERE a = 1 OR b = 'three' ORDER BY rowid }
} {I III 0 1}

do_test where8-1.7 { 
  execsql_status { SELECT c FROM t1 WHERE a = 1 OR b = 'three' ORDER BY a }