/*+
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** 2001 September 15+
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**+
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** The author disclaims copyright to this source code.  In place of+
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** a legal notice, here is a blessing:+
−
**+
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**    May you do good and not evil.+
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**    May you find forgiveness for yourself and forgive others.+
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**    May you share freely, never taking more than you give.+
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**+
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*************************************************************************+
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** This file contains routines used for analyzing expressions and+
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** for generating VDBE code that evaluates expressions in SQLite.+
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**+
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** $Id: expr.cpp 1282 2008-11-13 09:31:33Z LarsPson $+
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*/+
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#include "sqliteInt.h"+
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#include <ctype.h>+
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+
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/*+
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** Return the 'affinity' of the expression pExpr if any.+
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**+
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** If pExpr is a column, a reference to a column via an 'AS' alias,+
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** or a sub-select with a column as the return value, then the +
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** affinity of that column is returned. Otherwise, 0x00 is returned,+
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** indicating no affinity for the expression.+
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**+
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** i.e. the WHERE clause expresssions in the following statements all+
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** have an affinity:+
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**+
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** CREATE TABLE t1(a);+
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** SELECT * FROM t1 WHERE a;+
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** SELECT a AS b FROM t1 WHERE b;+
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** SELECT * FROM t1 WHERE (select a from t1);+
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*/+
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char sqlite3ExprAffinity(Expr *pExpr){+
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  int op = pExpr->op;+
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  if( op==TK_SELECT ){+
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    return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);+
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  }+
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#ifndef SQLITE_OMIT_CAST+
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  if( op==TK_CAST ){+
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    return sqlite3AffinityType(&pExpr->token);+
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  }+
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#endif+
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  return pExpr->affinity;+
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}+
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+
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/*+
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** Set the collating sequence for expression pExpr to be the collating+
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** sequence named by pToken.   Return a pointer to the revised expression.+
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** The collating sequence is marked as "explicit" using the EP_ExpCollate+
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** flag.  An explicit collating sequence will override implicit+
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** collating sequences.+
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*/+
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Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pName){+
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  char *zColl = 0;            /* Dequoted name of collation sequence */+
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  CollSeq *pColl;+
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  zColl = sqlite3NameFromToken(pParse->db, pName);+
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  if( pExpr && zColl ){+
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    pColl = sqlite3LocateCollSeq(pParse, zColl, -1);+
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    if( pColl ){+
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      pExpr->pColl = pColl;+
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      pExpr->flags |= EP_ExpCollate;+
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    }+
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  }+
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  sqlite3_free(zColl);+
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  return pExpr;+
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}+
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+
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/*+
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** Return the default collation sequence for the expression pExpr. If+
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** there is no default collation type, return 0.+
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*/+
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CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){+
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  CollSeq *pColl = 0;+
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  if( pExpr ){+
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    int op;+
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    pColl = pExpr->pColl;+
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    op = pExpr->op;+
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    if( (op==TK_CAST || op==TK_UPLUS) && !pColl ){+
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      return sqlite3ExprCollSeq(pParse, pExpr->pLeft);+
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    }+
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  }+
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  if( sqlite3CheckCollSeq(pParse, pColl) ){ +
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    pColl = 0;+
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  }+
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  return pColl;+
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}+
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+
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/*+
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** pExpr is an operand of a comparison operator.  aff2 is the+
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** type affinity of the other operand.  This routine returns the+
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** type affinity that should be used for the comparison operator.+
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*/+
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char sqlite3CompareAffinity(Expr *pExpr, char aff2){+
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  char aff1 = sqlite3ExprAffinity(pExpr);+
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  if( aff1 && aff2 ){+
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    /* Both sides of the comparison are columns. If one has numeric+
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    ** affinity, use that. Otherwise use no affinity.+
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    */+
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    if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){+
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      return SQLITE_AFF_NUMERIC;+
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    }else{+
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      return SQLITE_AFF_NONE;+
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    }+
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  }else if( !aff1 && !aff2 ){+
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    /* Neither side of the comparison is a column.  Compare the+
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    ** results directly.+
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    */+
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    return SQLITE_AFF_NONE;+
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  }else{+
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    /* One side is a column, the other is not. Use the columns affinity. */+
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    assert( aff1==0 || aff2==0 );+
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    return (aff1 + aff2);+
−
  }+
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}+
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+
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/*+
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** pExpr is a comparison operator.  Return the type affinity that should+
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** be applied to both operands prior to doing the comparison.+
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*/+
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static char comparisonAffinity(Expr *pExpr){+
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  char aff;+
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  assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||+
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          pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||+
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          pExpr->op==TK_NE );+
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  assert( pExpr->pLeft );+
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  aff = sqlite3ExprAffinity(pExpr->pLeft);+
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  if( pExpr->pRight ){+
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    aff = sqlite3CompareAffinity(pExpr->pRight, aff);+
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  }+
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  else if( pExpr->pSelect ){+
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    aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff);+
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  }+
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  else if( !aff ){+
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    aff = SQLITE_AFF_NONE;+
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  }+
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  return aff;+
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}+
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+
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/*+
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** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.+
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** idx_affinity is the affinity of an indexed column. Return true+
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** if the index with affinity idx_affinity may be used to implement+
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** the comparison in pExpr.+
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*/+
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int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){+
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  char aff = comparisonAffinity(pExpr);+
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  switch( aff ){+
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    case SQLITE_AFF_NONE:+
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      return 1;+
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    case SQLITE_AFF_TEXT:+
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      return idx_affinity==SQLITE_AFF_TEXT;+
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    default:+
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      return sqlite3IsNumericAffinity(idx_affinity);+
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  }+
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}+
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+
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/*+
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** Return the P1 value that should be used for a binary comparison+
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** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.+
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** If jumpIfNull is true, then set the low byte of the returned+
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** P1 value to tell the opcode to jump if either expression+
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** evaluates to NULL.+
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*/+
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static int binaryCompareP1(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){+
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  char aff = sqlite3ExprAffinity(pExpr2);+
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  return ((int)sqlite3CompareAffinity(pExpr1, aff))+(jumpIfNull?0x100:0);+
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}+
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+
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/*+
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** Return a pointer to the collation sequence that should be used by+
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** a binary comparison operator comparing pLeft and pRight.+
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**+
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** If the left hand expression has a collating sequence type, then it is+
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** used. Otherwise the collation sequence for the right hand expression+
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** is used, or the default (BINARY) if neither expression has a collating+
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** type.+
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**+
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** Argument pRight (but not pLeft) may be a null pointer. In this case,+
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** it is not considered.+
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*/+
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CollSeq *sqlite3BinaryCompareCollSeq(+
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  Parse *pParse, +
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  Expr *pLeft, +
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  Expr *pRight+
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){+
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  CollSeq *pColl;+
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  assert( pLeft );+
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  if( pLeft->flags & EP_ExpCollate ){+
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    assert( pLeft->pColl );+
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    pColl = pLeft->pColl;+
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  }else if( pRight && pRight->flags & EP_ExpCollate ){+
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    assert( pRight->pColl );+
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    pColl = pRight->pColl;+
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  }else{+
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    pColl = sqlite3ExprCollSeq(pParse, pLeft);+
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    if( !pColl ){+
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      pColl = sqlite3ExprCollSeq(pParse, pRight);+
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    }+
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  }+
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  return pColl;+
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}+
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+
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/*+
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** Generate code for a comparison operator.+
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*/+
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static int codeCompare(+
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  Parse *pParse,    /* The parsing (and code generating) context */+
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  Expr *pLeft,      /* The left operand */+
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  Expr *pRight,     /* The right operand */+
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  int opcode,       /* The comparison opcode */+
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  int dest,         /* Jump here if true.  */+
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  int jumpIfNull    /* If true, jump if either operand is NULL */+
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){+
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  int p1 = binaryCompareP1(pLeft, pRight, jumpIfNull);+
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  CollSeq *p3 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);+
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  return sqlite3VdbeOp3(pParse->pVdbe, opcode, p1, dest, (const char*)p3, P3_COLLSEQ);+
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}+
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+
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/*+
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** Construct a new expression node and return a pointer to it.  Memory+
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** for this node is obtained from sqlite3_malloc().  The calling function+
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** is responsible for making sure the node eventually gets freed.+
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*/+
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Expr *sqlite3Expr(+
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  sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */+
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  int op,                 /* Expression opcode */+
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  Expr *pLeft,            /* Left operand */+
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  Expr *pRight,           /* Right operand */+
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  const Token *pToken     /* Argument token */+
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){+
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  Expr *pNew;+
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  pNew = (Expr*)sqlite3DbMallocZero(db, sizeof(Expr));+
−
  if( pNew==0 ){+
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    /* When malloc fails, delete pLeft and pRight. Expressions passed to +
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    ** this function must always be allocated with sqlite3Expr() for this +
−
    ** reason. +
−
    */+
−
    sqlite3ExprDelete(pLeft);+
−
    sqlite3ExprDelete(pRight);+
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    return 0;+
−
  }+
−
  pNew->op = op;+
−
  pNew->pLeft = pLeft;+
−
  pNew->pRight = pRight;+
−
  pNew->iAgg = -1;+
−
  if( pToken ){+
−
    assert( pToken->dyn==0 );+
−
    pNew->span = pNew->token = *pToken;+
−
  }else if( pLeft ){+
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    if( pRight ){+
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      sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span);+
−
      if( pRight->flags & EP_ExpCollate ){+
−
        pNew->flags |= EP_ExpCollate;+
−
        pNew->pColl = pRight->pColl;+
−
      }+
−
    }+
−
    if( pLeft->flags & EP_ExpCollate ){+
−
      pNew->flags |= EP_ExpCollate;+
−
      pNew->pColl = pLeft->pColl;+
−
    }+
−
  }+
−
+
−
  sqlite3ExprSetHeight(pNew);+
−
  return pNew;+
−
}+
−
+
−
/*+
−
** Works like sqlite3Expr() except that it takes an extra Parse*+
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** argument and notifies the associated connection object if malloc fails.+
−
*/+
−
Expr *sqlite3PExpr(+
−
  Parse *pParse,          /* Parsing context */+
−
  int op,                 /* Expression opcode */+
−
  Expr *pLeft,            /* Left operand */+
−
  Expr *pRight,           /* Right operand */+
−
  const Token *pToken     /* Argument token */+
−
){+
−
  return sqlite3Expr(pParse->db, op, pLeft, pRight, pToken);+
−
}+
−
+
−
/*+
−
** When doing a nested parse, you can include terms in an expression+
−
** that look like this:   #0 #1 #2 ...  These terms refer to elements+
−
** on the stack.  "#0" means the top of the stack.+
−
** "#1" means the next down on the stack.  And so forth.+
−
**+
−
** This routine is called by the parser to deal with on of those terms.+
−
** It immediately generates code to store the value in a memory location.+
−
** The returns an expression that will code to extract the value from+
−
** that memory location as needed.+
−
*/+
−
Expr *sqlite3RegisterExpr(Parse *pParse, Token *pToken){+
−
  Vdbe *v = pParse->pVdbe;+
−
  Expr *p;+
−
  int depth;+
−
  if( pParse->nested==0 ){+
−
    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);+
−
    return sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);+
−
  }+
−
  if( v==0 ) return 0;+
−
  p = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, pToken);+
−
  if( p==0 ){+
−
    return 0;  /* Malloc failed */+
−
  }+
−
  depth = atoi((char*)&pToken->z[1]);+
−
  p->iTable = pParse->nMem++;+
−
  sqlite3VdbeAddOp(v, OP_Dup, depth, 0);+
−
  sqlite3VdbeAddOp(v, OP_MemStore, p->iTable, 1);+
−
  return p;+
−
}+
−
+
−
/*+
−
** Join two expressions using an AND operator.  If either expression is+
−
** NULL, then just return the other expression.+
−
*/+
−
Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){+
−
  if( pLeft==0 ){+
−
    return pRight;+
−
  }else if( pRight==0 ){+
−
    return pLeft;+
−
  }else{+
−
    return sqlite3Expr(db, TK_AND, pLeft, pRight, 0);+
−
  }+
−
}+
−
+
−
/*+
−
** Set the Expr.span field of the given expression to span all+
−
** text between the two given tokens.+
−
*/+
−
void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){+
−
  assert( pRight!=0 );+
−
  assert( pLeft!=0 );+
−
  if( pExpr && pRight->z && pLeft->z ){+
−
    assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 );+
−
    if( pLeft->dyn==0 && pRight->dyn==0 ){+
−
      pExpr->span.z = pLeft->z;+
−
      pExpr->span.n = pRight->n + (pRight->z - pLeft->z);+
−
    }else{+
−
      pExpr->span.z = 0;+
−
    }+
−
  }+
−
}+
−
+
−
/*+
−
** Construct a new expression node for a function with multiple+
−
** arguments.+
−
*/+
−
Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){+
−
  Expr *pNew;+
−
  assert( pToken );+
−
  pNew = (Expr*)sqlite3DbMallocZero(pParse->db, sizeof(Expr) );+
−
  if( pNew==0 ){+
−
    sqlite3ExprListDelete(pList); /* Avoid leaking memory when malloc fails */+
−
    return 0;+
−
  }+
−
  pNew->op = TK_FUNCTION;+
−
  pNew->pList = pList;+
−
  assert( pToken->dyn==0 );+
−
  pNew->token = *pToken;+
−
  pNew->span = pNew->token;+
−
+
−
  sqlite3ExprSetHeight(pNew);+
−
  return pNew;+
−
}+
−
+
−
/*+
−
** Assign a variable number to an expression that encodes a wildcard+
−
** in the original SQL statement.  +
−
**+
−
** Wildcards consisting of a single "?" are assigned the next sequential+
−
** variable number.+
−
**+
−
** Wildcards of the form "?nnn" are assigned the number "nnn".  We make+
−
** sure "nnn" is not too be to avoid a denial of service attack when+
−
** the SQL statement comes from an external source.+
−
**+
−
** Wildcards of the form ":aaa" or "$aaa" are assigned the same number+
−
** as the previous instance of the same wildcard.  Or if this is the first+
−
** instance of the wildcard, the next sequenial variable number is+
−
** assigned.+
−
*/+
−
void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){+
−
  Token *pToken;+
−
  sqlite3 *db = pParse->db;+
−
+
−
  if( pExpr==0 ) return;+
−
  pToken = &pExpr->token;+
−
  assert( pToken->n>=1 );+
−
  assert( pToken->z!=0 );+
−
  assert( pToken->z[0]!=0 );+
−
  if( pToken->n==1 ){+
−
    /* Wildcard of the form "?".  Assign the next variable number */+
−
    pExpr->iTable = ++pParse->nVar;+
−
  }else if( pToken->z[0]=='?' ){+
−
    /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and+
−
    ** use it as the variable number */+
−
    int i;+
−
    pExpr->iTable = i = atoi((char*)&pToken->z[1]);+
−
    if( i<1 || i>SQLITE_MAX_VARIABLE_NUMBER ){+
−
      sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",+
−
          SQLITE_MAX_VARIABLE_NUMBER);+
−
    }+
−
    if( i>pParse->nVar ){+
−
      pParse->nVar = i;+
−
    }+
−
  }else{+
−
    /* Wildcards of the form ":aaa" or "$aaa".  Reuse the same variable+
−
    ** number as the prior appearance of the same name, or if the name+
−
    ** has never appeared before, reuse the same variable number+
−
    */+
−
    int i, n;+
−
    n = pToken->n;+
−
    for(i=0; i<pParse->nVarExpr; i++){+
−
      Expr *pE;+
−
      if( (pE = pParse->apVarExpr[i])!=0+
−
          && pE->token.n==n+
−
          && memcmp(pE->token.z, pToken->z, n)==0 ){+
−
        pExpr->iTable = pE->iTable;+
−
        break;+
−
      }+
−
    }+
−
    if( i>=pParse->nVarExpr ){+
−
      pExpr->iTable = ++pParse->nVar;+
−
      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){+
−
        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;+
−
        pParse->apVarExpr =+
−
            (Expr**)sqlite3DbReallocOrFree(+
−
              db,+
−
              pParse->apVarExpr,+
−
              pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])+
−
            );+
−
      }+
−
      if( !db->mallocFailed ){+
−
        assert( pParse->apVarExpr!=0 );+
−
        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;+
−
      }+
−
    }+
−
  } +
−
  if( !pParse->nErr && pParse->nVar>SQLITE_MAX_VARIABLE_NUMBER ){+
−
    sqlite3ErrorMsg(pParse, "too many SQL variables");+
−
  }+
−
}+
−
+
−
/*+
−
** Recursively delete an expression tree.+
−
*/+
−
void sqlite3ExprDelete(Expr *p){+
−
  if( p==0 ) return;+
−
  if( p->span.dyn ) sqlite3_free((char*)p->span.z);+
−
  if( p->token.dyn ) sqlite3_free((char*)p->token.z);+
−
  sqlite3ExprDelete(p->pLeft);+
−
  sqlite3ExprDelete(p->pRight);+
−
  sqlite3ExprListDelete(p->pList);+
−
  sqlite3SelectDelete(p->pSelect);+
−
  sqlite3_free(p);+
−
}+
−
+
−
/*+
−
** The Expr.token field might be a string literal that is quoted.+
−
** If so, remove the quotation marks.+
−
*/+
−
void sqlite3DequoteExpr(sqlite3 *db, Expr *p){+
−
  if( ExprHasAnyProperty(p, EP_Dequoted) ){+
−
    return;+
−
  }+
−
  ExprSetProperty(p, EP_Dequoted);+
−
  if( p->token.dyn==0 ){+
−
    sqlite3TokenCopy(db, &p->token, &p->token);+
−
  }+
−
  sqlite3Dequote((char*)p->token.z);+
−
}+
−
+
−
+
−
/*+
−
** The following group of routines make deep copies of expressions,+
−
** expression lists, ID lists, and select statements.  The copies can+
−
** be deleted (by being passed to their respective ...Delete() routines)+
−
** without effecting the originals.+
−
**+
−
** The expression list, ID, and source lists return by sqlite3ExprListDup(),+
−
** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded +
−
** by subsequent calls to sqlite*ListAppend() routines.+
−
**+
−
** Any tables that the SrcList might point to are not duplicated.+
−
*/+
−
Expr *sqlite3ExprDup(sqlite3 *db, Expr *p){+
−
  Expr *pNew;+
−
  if( p==0 ) return 0;+
−
  pNew = (Expr*)sqlite3DbMallocRaw(db, sizeof(*p) );+
−
  if( pNew==0 ) return 0;+
−
  memcpy(pNew, p, sizeof(*pNew));+
−
  if( p->token.z!=0 ){+
−
    pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);+
−
    pNew->token.dyn = 1;+
−
  }else{+
−
    assert( pNew->token.z==0 );+
−
  }+
−
  pNew->span.z = 0;+
−
  pNew->pLeft = sqlite3ExprDup(db, p->pLeft);+
−
  pNew->pRight = sqlite3ExprDup(db, p->pRight);+
−
  pNew->pList = sqlite3ExprListDup(db, p->pList);+
−
  pNew->pSelect = sqlite3SelectDup(db, p->pSelect);+
−
  return pNew;+
−
}+
−
void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){+
−
  if( pTo->dyn ) sqlite3_free((char*)pTo->z);+
−
  if( pFrom->z ){+
−
    pTo->n = pFrom->n;+
−
    pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);+
−
    pTo->dyn = 1;+
−
  }else{+
−
    pTo->z = 0;+
−
  }+
−
}+
−
ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){+
−
  ExprList *pNew;+
−
  ExprList::ExprList_item *pItem, *pOldItem;+
−
  int i;+
−
  if( p==0 ) return 0;+
−
  pNew = (ExprList*)sqlite3DbMallocRaw(db, sizeof(*pNew) );+
−
  if( pNew==0 ) return 0;+
−
  pNew->iECursor = 0;+
−
  pNew->nExpr = pNew->nAlloc = p->nExpr;+
−
  pNew->a = pItem = (ExprList::ExprList_item*)sqlite3DbMallocRaw(db,  p->nExpr*sizeof(p->a[0]) );+
−
  if( pItem==0 ){+
−
    sqlite3_free(pNew);+
−
    return 0;+
−
  } +
−
  pOldItem = p->a;+
−
  for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){+
−
    Expr *pNewExpr, *pOldExpr;+
−
    pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);+
−
    if( pOldExpr->span.z!=0 && pNewExpr ){+
−
      /* Always make a copy of the span for top-level expressions in the+
−
      ** expression list.  The logic in SELECT processing that determines+
−
      ** the names of columns in the result set needs this information */+
−
      sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);+
−
    }+
−
    assert( pNewExpr==0 || pNewExpr->span.z!=0 +
−
            || pOldExpr->span.z==0+
−
            || db->mallocFailed );+
−
    pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);+
−
    pItem->sortOrder = pOldItem->sortOrder;+
−
    pItem->isAgg = pOldItem->isAgg;+
−
    pItem->done = 0;+
−
  }+
−
  return pNew;+
−
}+
−
+
−
/*+
−
** If cursors, triggers, views and subqueries are all omitted from+
−
** the build, then none of the following routines, except for +
−
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes+
−
** called with a NULL argument.+
−
*/+
−
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \+
−
 || !defined(SQLITE_OMIT_SUBQUERY)+
−
SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){+
−
  SrcList *pNew;+
−
  int i;+
−
  int nByte;+
−
  if( p==0 ) return 0;+
−
  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);+
−
  pNew = (SrcList*)sqlite3DbMallocRaw(db, nByte );+
−
  if( pNew==0 ) return 0;+
−
  pNew->nSrc = pNew->nAlloc = p->nSrc;+
−
  for(i=0; i<p->nSrc; i++){+
−
	  SrcList::SrcList_item *pNewItem = &pNew->a[i];+
−
	  SrcList::SrcList_item *pOldItem = &p->a[i];+
−
    Table *pTab;+
−
    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);+
−
    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);+
−
    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);+
−
    pNewItem->jointype = pOldItem->jointype;+
−
    pNewItem->iCursor = pOldItem->iCursor;+
−
    pNewItem->isPopulated = pOldItem->isPopulated;+
−
    pTab = pNewItem->pTab = pOldItem->pTab;+
−
    if( pTab ){+
−
      pTab->nRef++;+
−
    }+
−
    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);+
−
    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);+
−
    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);+
−
    pNewItem->colUsed = pOldItem->colUsed;+
−
  }+
−
  return pNew;+
−
}+
−
IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){+
−
  IdList *pNew;+
−
  int i;+
−
  if( p==0 ) return 0;+
−
  pNew = (IdList*)sqlite3DbMallocRaw(db, sizeof(*pNew) );+
−
  if( pNew==0 ) return 0;+
−
  pNew->nId = pNew->nAlloc = p->nId;+
−
  pNew->a = (IdList::IdList_item*)sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );+
−
  if( pNew->a==0 ){+
−
    sqlite3_free(pNew);+
−
    return 0;+
−
  }+
−
  for(i=0; i<p->nId; i++){+
−
	  IdList::IdList_item *pNewItem = &pNew->a[i];+
−
	  IdList::IdList_item *pOldItem = &p->a[i];+
−
    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);+
−
    pNewItem->idx = pOldItem->idx;+
−
  }+
−
  return pNew;+
−
}+
−
Select *sqlite3SelectDup(sqlite3 *db, Select *p){+
−
  Select *pNew;+
−
  if( p==0 ) return 0;+
−
  pNew = (Select*)sqlite3DbMallocRaw(db, sizeof(*p) );+
−
  if( pNew==0 ) return 0;+
−
  pNew->isDistinct = p->isDistinct;+
−
  pNew->pEList = sqlite3ExprListDup(db, p->pEList);+
−
  pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);+
−
  pNew->pWhere = sqlite3ExprDup(db, p->pWhere);+
−
  pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);+
−
  pNew->pHaving = sqlite3ExprDup(db, p->pHaving);+
−
  pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);+
−
  pNew->op = p->op;+
−
  pNew->pPrior = sqlite3SelectDup(db, p->pPrior);+
−
  pNew->pLimit = sqlite3ExprDup(db, p->pLimit);+
−
  pNew->pOffset = sqlite3ExprDup(db, p->pOffset);+
−
  pNew->iLimit = -1;+
−
  pNew->iOffset = -1;+
−
  pNew->isResolved = p->isResolved;+
−
  pNew->isAgg = p->isAgg;+
−
  pNew->usesEphm = 0;+
−
  pNew->disallowOrderBy = 0;+
−
  pNew->pRightmost = 0;+
−
  pNew->addrOpenEphm[0] = -1;+
−
  pNew->addrOpenEphm[1] = -1;+
−
  pNew->addrOpenEphm[2] = -1;+
−
  return pNew;+
−
}+
−
#else+
−
Select *sqlite3SelectDup(sqlite3 *db, Select *p){+
−
  assert( p==0 );+
−
  return 0;+
−
}+
−
#endif+
−
+
−
+
−
/*+
−
** Add a new element to the end of an expression list.  If pList is+
−
** initially NULL, then create a new expression list.+
−
*/+
−
ExprList *sqlite3ExprListAppend(+
−
  Parse *pParse,          /* Parsing context */+
−
  ExprList *pList,        /* List to which to append. Might be NULL */+
−
  Expr *pExpr,            /* Expression to be appended */+
−
  Token *pName            /* AS keyword for the expression */+
−
){+
−
  sqlite3 *db = pParse->db;+
−
  if( pList==0 ){+
−
    pList = (ExprList*)sqlite3DbMallocZero(db, sizeof(ExprList) );+
−
    if( pList==0 ){+
−
      goto no_mem;+
−
    }+
−
    assert( pList->nAlloc==0 );+
−
  }+
−
  if( pList->nAlloc<=pList->nExpr ){+
−
	  ExprList::ExprList_item *a;+
−
    int n = pList->nAlloc*2 + 4;+
−
	a = (ExprList::ExprList_item*)sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));+
−
    if( a==0 ){+
−
      goto no_mem;+
−
    }+
−
    pList->a = a;+
−
    pList->nAlloc = n;+
−
  }+
−
  assert( pList->a!=0 );+
−
  if( pExpr || pName ){+
−
	  ExprList::ExprList_item *pItem = &pList->a[pList->nExpr++];+
−
    memset(pItem, 0, sizeof(*pItem));+
−
    pItem->zName = sqlite3NameFromToken(db, pName);+
−
    pItem->pExpr = pExpr;+
−
  }+
−
  return pList;+
−
+
−
no_mem:     +
−
  /* Avoid leaking memory if malloc has failed. */+
−
  sqlite3ExprDelete(pExpr);+
−
  sqlite3ExprListDelete(pList);+
−
  return 0;+
−
}+
−
+
−
/*+
−
** If the expression list pEList contains more than iLimit elements,+
−
** leave an error message in pParse.+
−
*/+
−
void sqlite3ExprListCheckLength(+
−
  Parse *pParse,+
−
  ExprList *pEList,+
−
  int iLimit,+
−
  const char *zObject+
−
){+
−
  if( pEList && pEList->nExpr>iLimit ){+
−
    sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);+
−
  }+
−
}+
−
+
−
+
−
#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0+
−
/* The following three functions, heightOfExpr(), heightOfExprList()+
−
** and heightOfSelect(), are used to determine the maximum height+
−
** of any expression tree referenced by the structure passed as the+
−
** first argument.+
−
**+
−
** If this maximum height is greater than the current value pointed+
−
** to by pnHeight, the second parameter, then set *pnHeight to that+
−
** value.+
−
*/+
−
static void heightOfExpr(Expr *p, int *pnHeight){+
−
  if( p ){+
−
    if( p->nHeight>*pnHeight ){+
−
      *pnHeight = p->nHeight;+
−
    }+
−
  }+
−
}+
−
static void heightOfExprList(ExprList *p, int *pnHeight){+
−
  if( p ){+
−
    int i;+
−
    for(i=0; i<p->nExpr; i++){+
−
      heightOfExpr(p->a[i].pExpr, pnHeight);+
−
    }+
−
  }+
−
}+
−
static void heightOfSelect(Select *p, int *pnHeight){+
−
  if( p ){+
−
    heightOfExpr(p->pWhere, pnHeight);+
−
    heightOfExpr(p->pHaving, pnHeight);+
−
    heightOfExpr(p->pLimit, pnHeight);+
−
    heightOfExpr(p->pOffset, pnHeight);+
−
    heightOfExprList(p->pEList, pnHeight);+
−
    heightOfExprList(p->pGroupBy, pnHeight);+
−
    heightOfExprList(p->pOrderBy, pnHeight);+
−
    heightOfSelect(p->pPrior, pnHeight);+
−
  }+
−
}+
−
+
−
/*+
−
** Set the Expr.nHeight variable in the structure passed as an +
−
** argument. An expression with no children, Expr.pList or +
−
** Expr.pSelect member has a height of 1. Any other expression+
−
** has a height equal to the maximum height of any other +
−
** referenced Expr plus one.+
−
*/+
−
void sqlite3ExprSetHeight(Expr *p){+
−
  int nHeight = 0;+
−
  heightOfExpr(p->pLeft, &nHeight);+
−
  heightOfExpr(p->pRight, &nHeight);+
−
  heightOfExprList(p->pList, &nHeight);+
−
  heightOfSelect(p->pSelect, &nHeight);+
−
  p->nHeight = nHeight + 1;+
−
}+
−
+
−
/*+
−
** Return the maximum height of any expression tree referenced+
−
** by the select statement passed as an argument.+
−
*/+
−
int sqlite3SelectExprHeight(Select *p){+
−
  int nHeight = 0;+
−
  heightOfSelect(p, &nHeight);+
−
  return nHeight;+
−
}+
−
#endif+
−
+
−
/*+
−
** Delete an entire expression list.+
−
*/+
−
void sqlite3ExprListDelete(ExprList *pList){+
−
  int i;+
−
  ExprList::ExprList_item *pItem;+
−
  if( pList==0 ) return;+
−
  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );+
−
  assert( pList->nExpr<=pList->nAlloc );+
−
  for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){+
−
    sqlite3ExprDelete(pItem->pExpr);+
−
    sqlite3_free(pItem->zName);+
−
  }+
−
  sqlite3_free(pList->a);+
−
  sqlite3_free(pList);+
−
}+
−
+
−
/*+
−
** Walk an expression tree.  Call xFunc for each node visited.+
−
**+
−
** The return value from xFunc determines whether the tree walk continues.+
−
** 0 means continue walking the tree.  1 means do not walk children+
−
** of the current node but continue with siblings.  2 means abandon+
−
** the tree walk completely.+
−
**+
−
** The return value from this routine is 1 to abandon the tree walk+
−
** and 0 to continue.+
−
**+
−
** NOTICE:  This routine does *not* descend into subqueries.+
−
*/+
−
static int walkExprList(ExprList *, int (*)(void *, Expr*), void *);+
−
static int walkExprTree(Expr *pExpr, int (*xFunc)(void*,Expr*), void *pArg){+
−
  int rc;+
−
  if( pExpr==0 ) return 0;+
−
  rc = (*xFunc)(pArg, pExpr);+
−
  if( rc==0 ){+
−
    if( walkExprTree(pExpr->pLeft, xFunc, pArg) ) return 1;+
−
    if( walkExprTree(pExpr->pRight, xFunc, pArg) ) return 1;+
−
    if( walkExprList(pExpr->pList, xFunc, pArg) ) return 1;+
−
  }+
−
  return rc>1;+
−
}+
−
+
−
/*+
−
** Call walkExprTree() for every expression in list p.+
−
*/+
−
static int walkExprList(ExprList *p, int (*xFunc)(void *, Expr*), void *pArg){+
−
  int i;+
−
  ExprList::ExprList_item *pItem;+
−
  if( !p ) return 0;+
−
  for(i=p->nExpr, pItem=p->a; i>0; i--, pItem++){+
−
    if( walkExprTree(pItem->pExpr, xFunc, pArg) ) return 1;+
−
  }+
−
  return 0;+
−
}+
−
+
−
/*+
−
** Call walkExprTree() for every expression in Select p, not including+
−
** expressions that are part of sub-selects in any FROM clause or the LIMIT+
−
** or OFFSET expressions..+
−
*/+
−
static int walkSelectExpr(Select *p, int (*xFunc)(void *, Expr*), void *pArg){+
−
  walkExprList(p->pEList, xFunc, pArg);+
−
  walkExprTree(p->pWhere, xFunc, pArg);+
−
  walkExprList(p->pGroupBy, xFunc, pArg);+
−
  walkExprTree(p->pHaving, xFunc, pArg);+
−
  walkExprList(p->pOrderBy, xFunc, pArg);+
−
  if( p->pPrior ){+
−
    walkSelectExpr(p->pPrior, xFunc, pArg);+
−
  }+
−
  return 0;+
−
}+
−
+
−
+
−
/*+
−
** This routine is designed as an xFunc for walkExprTree().+
−
**+
−
** pArg is really a pointer to an integer.  If we can tell by looking+
−
** at pExpr that the expression that contains pExpr is not a constant+
−
** expression, then set *pArg to 0 and return 2 to abandon the tree walk.+
−
** If pExpr does does not disqualify the expression from being a constant+
−
** then do nothing.+
−
**+
−
** After walking the whole tree, if no nodes are found that disqualify+
−
** the expression as constant, then we assume the whole expression+
−
** is constant.  See sqlite3ExprIsConstant() for additional information.+
−
*/+
−
static int exprNodeIsConstant(void *pArg, Expr *pExpr){+
−
  int *pN = (int*)pArg;+
−
+
−
  /* If *pArg is 3 then any term of the expression that comes from+
−
  ** the ON or USING clauses of a join disqualifies the expression+
−
  ** from being considered constant. */+
−
  if( (*pN)==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){+
−
    *pN = 0;+
−
    return 2;+
−
  }+
−
+
−
  switch( pExpr->op ){+
−
    /* Consider functions to be constant if all their arguments are constant+
−
    ** and *pArg==2 */+
−
    case TK_FUNCTION:+
−
      if( (*pN)==2 ) return 0;+
−
      /* Fall through */+
−
    case TK_ID:+
−
    case TK_COLUMN:+
−
    case TK_DOT:+
−
    case TK_AGG_FUNCTION:+
−
    case TK_AGG_COLUMN:+
−
#ifndef SQLITE_OMIT_SUBQUERY+
−
    case TK_SELECT:+
−
    case TK_EXISTS:+
−
#endif+
−
      *pN = 0;+
−
      return 2;+
−
    case TK_IN:+
−
      if( pExpr->pSelect ){+
−
        *pN = 0;+
−
        return 2;+
−
      }+
−
    default:+
−
      return 0;+
−
  }+
−
}+
−
+
−
/*+
−
** Walk an expression tree.  Return 1 if the expression is constant+
−
** and 0 if it involves variables or function calls.+
−
**+
−
** For the purposes of this function, a double-quoted string (ex: "abc")+
−
** is considered a variable but a single-quoted string (ex: 'abc') is+
−
** a constant.+
−
*/+
−
int sqlite3ExprIsConstant(Expr *p){+
−
  int isConst = 1;+
−
  walkExprTree(p, exprNodeIsConstant, &isConst);+
−
  return isConst;+
−
}+
−
+
−
/*+
−
** Walk an expression tree.  Return 1 if the expression is constant+
−
** that does no originate from the ON or USING clauses of a join.+
−
** Return 0 if it involves variables or function calls or terms from+
−
** an ON or USING clause.+
−
*/+
−
int sqlite3ExprIsConstantNotJoin(Expr *p){+
−
  int isConst = 3;+
−
  walkExprTree(p, exprNodeIsConstant, &isConst);+
−
  return isConst!=0;+
−
}+
−
+
−
/*+
−
** Walk an expression tree.  Return 1 if the expression is constant+
−
** or a function call with constant arguments.  Return and 0 if there+
−
** are any variables.+
−
**+
−
** For the purposes of this function, a double-quoted string (ex: "abc")+
−
** is considered a variable but a single-quoted string (ex: 'abc') is+
−
** a constant.+
−
*/+
−
int sqlite3ExprIsConstantOrFunction(Expr *p){+
−
  int isConst = 2;+
−
  walkExprTree(p, exprNodeIsConstant, &isConst);+
−
  return isConst!=0;+
−
}+
−
+
−
/*+
−
** If the expression p codes a constant integer that is small enough+
−
** to fit in a 32-bit integer, return 1 and put the value of the integer+
−
** in *pValue.  If the expression is not an integer or if it is too big+
−
** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.+
−
*/+
−
int sqlite3ExprIsInteger(Expr *p, int *pValue){+
−
  switch( p->op ){+
−
    case TK_INTEGER: {+
−
      if( sqlite3GetInt32((char*)p->token.z, pValue) ){+
−
        return 1;+
−
      }+
−
      break;+
−
    }+
−
    case TK_UPLUS: {+
−
      return sqlite3ExprIsInteger(p->pLeft, pValue);+
−
    }+
−
    case TK_UMINUS: {+
−
      int v;+
−
      if( sqlite3ExprIsInteger(p->pLeft, &v) ){+
−
        *pValue = -v;+
−
        return 1;+
−
      }+
−
      break;+
−
    }+
−
    default: break;+
−
  }+
−
  return 0;+
−
}+
−
+
−
/*+
−
** Return TRUE if the given string is a row-id column name.+
−
*/+
−
int sqlite3IsRowid(const char *z){+
−
  if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;+
−
  if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;+
−
  if( sqlite3StrICmp(z, "OID")==0 ) return 1;+
−
  return 0;+
−
}+
−
+
−
/*+
−
** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up+
−
** that name in the set of source tables in pSrcList and make the pExpr +
−
** expression node refer back to that source column.  The following changes+
−
** are made to pExpr:+
−
**+
−
**    pExpr->iDb           Set the index in db->aDb[] of the database holding+
−
**                         the table.+
−
**    pExpr->iTable        Set to the cursor number for the table obtained+
−
**                         from pSrcList.+
−
**    pExpr->iColumn       Set to the column number within the table.+
−
**    pExpr->op            Set to TK_COLUMN.+
−
**    pExpr->pLeft         Any expression this points to is deleted+
−
**    pExpr->pRight        Any expression this points to is deleted.+
−
**+
−
** The pDbToken is the name of the database (the "X").  This value may be+
−
** NULL meaning that name is of the form Y.Z or Z.  Any available database+
−
** can be used.  The pTableToken is the name of the table (the "Y").  This+
−
** value can be NULL if pDbToken is also NULL.  If pTableToken is NULL it+
−
** means that the form of the name is Z and that columns from any table+
−
** can be used.+
−
**+
−
** If the name cannot be resolved unambiguously, leave an error message+
−
** in pParse and return non-zero.  Return zero on success.+
−
*/+
−
static int lookupName(+
−
  Parse *pParse,       /* The parsing context */+
−
  Token *pDbToken,     /* Name of the database containing table, or NULL */+
−
  Token *pTableToken,  /* Name of table containing column, or NULL */+
−
  Token *pColumnToken, /* Name of the column. */+
−
  NameContext *pNC,    /* The name context used to resolve the name */+
−
  Expr *pExpr          /* Make this EXPR node point to the selected column */+
−
){+
−
  char *zDb = 0;       /* Name of the database.  The "X" in X.Y.Z */+
−
  char *zTab = 0;      /* Name of the table.  The "Y" in X.Y.Z or Y.Z */+
−
  char *zCol = 0;      /* Name of the column.  The "Z" */+
−
  int i, j;            /* Loop counters */+
−
  int cnt = 0;         /* Number of matching column names */+
−
  int cntTab = 0;      /* Number of matching table names */+
−
  sqlite3 *db = pParse->db;  /* The database */+
−
  SrcList::SrcList_item *pItem;       /* Use for looping over pSrcList items */+
−
  SrcList::SrcList_item *pMatch = 0;  /* The matching pSrcList item */+
−
  NameContext *pTopNC = pNC;        /* First namecontext in the list */+
−
  Schema *pSchema = 0;              /* Schema of the expression */+
−
+
−
  assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */+
−
  zDb = sqlite3NameFromToken(db, pDbToken);+
−
  zTab = sqlite3NameFromToken(db, pTableToken);+
−
  zCol = sqlite3NameFromToken(db, pColumnToken);+
−
  if( db->mallocFailed ){+
−
    goto lookupname_end;+
−
  }+
−
+
−
  pExpr->iTable = -1;+
−
  while( pNC && cnt==0 ){+
−
    ExprList *pEList;+
−
    SrcList *pSrcList = pNC->pSrcList;+
−
+
−
    if( pSrcList ){+
−
      for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){+
−
        Table *pTab;+
−
        int iDb;+
−
        Column *pCol;+
−
  +
−
        pTab = pItem->pTab;+
−
        assert( pTab!=0 );+
−
        iDb = sqlite3SchemaToIndex(db, pTab->pSchema);+
−
        assert( pTab->nCol>0 );+
−
        if( zTab ){+
−
          if( pItem->zAlias ){+
−
            char *zTabName = pItem->zAlias;+
−
            if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;+
−
          }else{+
−
            char *zTabName = pTab->zName;+
−
            if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;+
−
            if( zDb!=0 && sqlite3StrICmp(db->aDb[iDb].zName, zDb)!=0 ){+
−
              continue;+
−
            }+
−
          }+
−
        }+
−
        if( 0==(cntTab++) ){+
−
          pExpr->iTable = pItem->iCursor;+
−
          pSchema = pTab->pSchema;+
−
          pMatch = pItem;+
−
        }+
−
        for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){+
−
          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){+
−
            const char *zColl = pTab->aCol[j].zColl;+
−
            IdList *pUsing;+
−
            cnt++;+
−
            pExpr->iTable = pItem->iCursor;+
−
            pMatch = pItem;+
−
            pSchema = pTab->pSchema;+
−
            /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */+
−
            pExpr->iColumn = j==pTab->iPKey ? -1 : j;+
−
            pExpr->affinity = pTab->aCol[j].affinity;+
−
            if( (pExpr->flags & EP_ExpCollate)==0 ){+
−
              pExpr->pColl = sqlite3FindCollSeq(db, ENC(db), zColl,-1, 0);+
−
            }+
−
            if( i<pSrcList->nSrc-1 ){+
−
              if( pItem[1].jointype & JT_NATURAL ){+
−
                /* If this match occurred in the left table of a natural join,+
−
                ** then skip the right table to avoid a duplicate match */+
−
                pItem++;+
−
                i++;+
−
              }else if( (pUsing = pItem[1].pUsing)!=0 ){+
−
                /* If this match occurs on a column that is in the USING clause+
−
                ** of a join, skip the search of the right table of the join+
−
                ** to avoid a duplicate match there. */+
−
                int k;+
−
                for(k=0; k<pUsing->nId; k++){+
−
                  if( sqlite3StrICmp(pUsing->a[k].zName, zCol)==0 ){+
−
                    pItem++;+
−
                    i++;+
−
                    break;+
−
                  }+
−
                }+
−
              }+
−
            }+
−
            break;+
−
          }+
−
        }+
−
      }+
−
    }+
−
+
−
#ifndef SQLITE_OMIT_TRIGGER+
−
    /* If we have not already resolved the name, then maybe +
−
    ** it is a new.* or old.* trigger argument reference+
−
    */+
−
    if( zDb==0 && zTab!=0 && cnt==0 && pParse->trigStack!=0 ){+
−
      TriggerStack *pTriggerStack = pParse->trigStack;+
−
      Table *pTab = 0;+
−
      if( pTriggerStack->newIdx != -1 && sqlite3StrICmp("new", zTab) == 0 ){+
−
        pExpr->iTable = pTriggerStack->newIdx;+
−
        assert( pTriggerStack->pTab );+
−
        pTab = pTriggerStack->pTab;+
−
      }else if( pTriggerStack->oldIdx != -1 && sqlite3StrICmp("old", zTab)==0 ){+
−
        pExpr->iTable = pTriggerStack->oldIdx;+
−
        assert( pTriggerStack->pTab );+
−
        pTab = pTriggerStack->pTab;+
−
      }+
−
+
−
      if( pTab ){ +
−
        int iCol;+
−
        Column *pCol = pTab->aCol;+
−
+
−
        pSchema = pTab->pSchema;+
−
        cntTab++;+
−
        for(iCol=0; iCol < pTab->nCol; iCol++, pCol++) {+
−
          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){+
−
            const char *zColl = pTab->aCol[iCol].zColl;+
−
            cnt++;+
−
            pExpr->iColumn = iCol==pTab->iPKey ? -1 : iCol;+
−
            pExpr->affinity = pTab->aCol[iCol].affinity;+
−
            if( (pExpr->flags & EP_ExpCollate)==0 ){+
−
              pExpr->pColl = sqlite3FindCollSeq(db, ENC(db), zColl,-1, 0);+
−
            }+
−
            pExpr->pTab = pTab;+
−
            break;+
−
          }+
−
        }+
−
      }+
−
    }+
−
#endif /* !defined(SQLITE_OMIT_TRIGGER) */+
−
+
−
    /*+
−
    ** Perhaps the name is a reference to the ROWID+
−
    */+
−
    if( cnt==0 && cntTab==1 && sqlite3IsRowid(zCol) ){+
−
      cnt = 1;+
−
      pExpr->iColumn = -1;+
−
      pExpr->affinity = SQLITE_AFF_INTEGER;+
−
    }+
−
+
−
    /*+
−
    ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z+
−
    ** might refer to an result-set alias.  This happens, for example, when+
−
    ** we are resolving names in the WHERE clause of the following command:+
−
    **+
−
    **     SELECT a+b AS x FROM table WHERE x<10;+
−
    **+
−
    ** In cases like this, replace pExpr with a copy of the expression that+
−
    ** forms the result set entry ("a+b" in the example) and return immediately.+
−
    ** Note that the expression in the result set should have already been+
−
    ** resolved by the time the WHERE clause is resolved.+
−
    */+
−
    if( cnt==0 && (pEList = pNC->pEList)!=0 && zTab==0 ){+
−
      for(j=0; j<pEList->nExpr; j++){+
−
        char *zAs = pEList->a[j].zName;+
−
        if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){+
−
          Expr *pDup, *pOrig;+
−
          assert( pExpr->pLeft==0 && pExpr->pRight==0 );+
−
          assert( pExpr->pList==0 );+
−
          assert( pExpr->pSelect==0 );+
−
          pOrig = pEList->a[j].pExpr;+
−
          if( !pNC->allowAgg && ExprHasProperty(pOrig, EP_Agg) ){+
−
            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);+
−
            sqlite3_free(zCol);+
−
            return 2;+
−
          }+
−
          pDup = sqlite3ExprDup(db, pOrig);+
−
          if( pExpr->flags & EP_ExpCollate ){+
−
            pDup->pColl = pExpr->pColl;+
−
            pDup->flags |= EP_ExpCollate;+
−
          }+
−
          if( pExpr->span.dyn ) sqlite3_free((char*)pExpr->span.z);+
−
          if( pExpr->token.dyn ) sqlite3_free((char*)pExpr->token.z);+
−
          memcpy(pExpr, pDup, sizeof(*pExpr));+
−
          sqlite3_free(pDup);+
−
          cnt = 1;+
−
          pMatch = 0;+
−
          assert( zTab==0 && zDb==0 );+
−
          goto lookupname_end_2;+
−
        }+
−
      } +
−
    }+
−
+
−
    /* Advance to the next name context.  The loop will exit when either+
−
    ** we have a match (cnt>0) or when we run out of name contexts.+
−
    */+
−
    if( cnt==0 ){+
−
      pNC = pNC->pNext;+
−
    }+
−
  }+
−
+
−
  /*+
−
  ** If X and Y are NULL (in other words if only the column name Z is+
−
  ** supplied) and the value of Z is enclosed in double-quotes, then+
−
  ** Z is a string literal if it doesn't match any column names.  In that+
−
  ** case, we need to return right away and not make any changes to+
−
  ** pExpr.+
−
  **+
−
  ** Because no reference was made to outer contexts, the pNC->nRef+
−
  ** fields are not changed in any context.+
−
  */+
−
  if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){+
−
    sqlite3_free(zCol);+
−
    return 0;+
−
  }+
−
+
−
  /*+
−
  ** cnt==0 means there was not match.  cnt>1 means there were two or+
−
  ** more matches.  Either way, we have an error.+
−
  */+
−
  if( cnt!=1 ){+
−
    char *z = 0;+
−
    char *zErr;+
−
    zErr = (char*)(cnt==0 ? "no such column: %s" : "ambiguous column name: %s");+
−
    if( zDb ){+
−
      sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, (char*)0);+
−
    }else if( zTab ){+
−
      sqlite3SetString(&z, zTab, ".", zCol, (char*)0);+
−
    }else{+
−
      z = sqlite3StrDup(zCol);+
−
    }+
−
    if( z ){+
−
      sqlite3ErrorMsg(pParse, zErr, z);+
−
      sqlite3_free(z);+
−
      pTopNC->nErr++;+
−
    }else{+
−
      db->mallocFailed = 1;+
−
    }+
−
  }+
−
+
−
  /* If a column from a table in pSrcList is referenced, then record+
−
  ** this fact in the pSrcList.a[].colUsed bitmask.  Column 0 causes+
−
  ** bit 0 to be set.  Column 1 sets bit 1.  And so forth.  If the+
−
  ** column number is greater than the number of bits in the bitmask+
−
  ** then set the high-order bit of the bitmask.+
−
  */+
−
  if( pExpr->iColumn>=0 && pMatch!=0 ){+
−
    int n = pExpr->iColumn;+
−
    if( n>=sizeof(Bitmask)*8 ){+
−
      n = sizeof(Bitmask)*8-1;+
−
    }+
−
    assert( pMatch->iCursor==pExpr->iTable );+
−
    pMatch->colUsed |= ((Bitmask)1)<<n;+
−
  }+
−
+
−
lookupname_end:+
−
  /* Clean up and return+
−
  */+
−
  sqlite3_free(zDb);+
−
  sqlite3_free(zTab);+
−
  sqlite3ExprDelete(pExpr->pLeft);+
−
  pExpr->pLeft = 0;+
−
  sqlite3ExprDelete(pExpr->pRight);+
−
  pExpr->pRight = 0;+
−
  pExpr->op = TK_COLUMN;+
−
lookupname_end_2:+
−
  sqlite3_free(zCol);+
−
  if( cnt==1 ){+
−
    assert( pNC!=0 );+
−
    sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);+
−
    if( pMatch && !pMatch->pSelect ){+
−
      pExpr->pTab = pMatch->pTab;+
−
    }+
−
    /* Increment the nRef value on all name contexts from TopNC up to+
−
    ** the point where the name matched. */+
−
    for(;;){+
−
      assert( pTopNC!=0 );+
−
      pTopNC->nRef++;+
−
      if( pTopNC==pNC ) break;+
−
      pTopNC = pTopNC->pNext;+
−
    }+
−
    return 0;+
−
  } else {+
−
    return 1;+
−
  }+
−
}+
−
+
−
/*+
−
** This routine is designed as an xFunc for walkExprTree().+
−
**+
−
** Resolve symbolic names into TK_COLUMN operators for the current+
−
** node in the expression tree.  Return 0 to continue the search down+
−
** the tree or 2 to abort the tree walk.+
−
**+
−
** This routine also does error checking and name resolution for+
−
** function names.  The operator for aggregate functions is changed+
−
** to TK_AGG_FUNCTION.+
−
*/+
−
static int nameResolverStep(void *pArg, Expr *pExpr){+
−
  NameContext *pNC = (NameContext*)pArg;+
−
  Parse *pParse;+
−
+
−
  if( pExpr==0 ) return 1;+
−
  assert( pNC!=0 );+
−
  pParse = pNC->pParse;+
−
+
−
  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1;+
−
  ExprSetProperty(pExpr, EP_Resolved);+
−
#ifndef NDEBUG+
−
  if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){+
−
    SrcList *pSrcList = pNC->pSrcList;+
−
    int i;+
−
    for(i=0; i<pNC->pSrcList->nSrc; i++){+
−
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);+
−
    }+
−
  }+
−
#endif+
−
  switch( pExpr->op ){+
−
    /* Double-quoted strings (ex: "abc") are used as identifiers if+
−
    ** possible.  Otherwise they remain as strings.  Single-quoted+
−
    ** strings (ex: 'abc') are always string literals.+
−
    */+
−
    case TK_STRING: {+
−
      if( pExpr->token.z[0]=='\'' ) break;+
−
      /* Fall thru into the TK_ID case if this is a double-quoted string */+
−
    }+
−
    /* A lone identifier is the name of a column.+
−
    */+
−
    case TK_ID: {+
−
      lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);+
−
      return 1;+
−
    }+
−
  +
−
    /* A table name and column name:     ID.ID+
−
    ** Or a database, table and column:  ID.ID.ID+
−
    */+
−
    case TK_DOT: {+
−
      Token *pColumn;+
−
      Token *pTable;+
−
      Token *pDb;+
−
      Expr *pRight;+
−
+
−
      /* if( pSrcList==0 ) break; */+
−
      pRight = pExpr->pRight;+
−
      if( pRight->op==TK_ID ){+
−
        pDb = 0;+
−
        pTable = &pExpr->pLeft->token;+
−
        pColumn = &pRight->token;+
−
      }else{+
−
        assert( pRight->op==TK_DOT );+
−
        pDb = &pExpr->pLeft->token;+
−
        pTable = &pRight->pLeft->token;+
−
        pColumn = &pRight->pRight->token;+
−
      }+
−
      lookupName(pParse, pDb, pTable, pColumn, pNC, pExpr);+
−
      return 1;+
−
    }+
−
+
−
    /* Resolve function names+
−
    */+
−
    case TK_CONST_FUNC:+
−
    case TK_FUNCTION: {+
−
      ExprList *pList = pExpr->pList;    /* The argument list */+
−
      int n = pList ? pList->nExpr : 0;  /* Number of arguments */+
−
      int no_such_func = 0;       /* True if no such function exists */+
−
      int wrong_num_args = 0;     /* True if wrong number of arguments */+
−
      int is_agg = 0;             /* True if is an aggregate function */+
−
      int i;+
−
      int auth;                   /* Authorization to use the function */+
−
      int nId;                    /* Number of characters in function name */+
−
      const char *zId;            /* The function name. */+
−
      FuncDef *pDef;              /* Information about the function */+
−
      int enc = ENC(pParse->db);  /* The database encoding */+
−
+
−
      zId = (char*)pExpr->token.z;+
−
      nId = pExpr->token.n;+
−
      pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);+
−
      if( pDef==0 ){+
−
        pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, enc, 0);+
−
        if( pDef==0 ){+
−
          no_such_func = 1;+
−
        }else{+
−
          wrong_num_args = 1;+
−
        }+
−
      }else{+
−
        is_agg = pDef->xFunc==0;+
−
      }+
−
#ifndef SQLITE_OMIT_AUTHORIZATION+
−
      if( pDef ){+
−
        auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0);+
−
        if( auth!=SQLITE_OK ){+
−
          if( auth==SQLITE_DENY ){+
−
            sqlite3ErrorMsg(pParse, "not authorized to use function: %s",+
−
                                    pDef->zName);+
−
            pNC->nErr++;+
−
          }+
−
          pExpr->op = TK_NULL;+
−
          return 1;+
−
        }+
−
      }+
−
#endif+
−
      if( is_agg && !pNC->allowAgg ){+
−
        sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId);+
−
        pNC->nErr++;+
−
        is_agg = 0;+
−
      }else if( no_such_func ){+
−
        sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);+
−
        pNC->nErr++;+
−
      }else if( wrong_num_args ){+
−
        sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",+
−
             nId, zId);+
−
        pNC->nErr++;+
−
      }+
−
      if( is_agg ){+
−
        pExpr->op = TK_AGG_FUNCTION;+
−
        pNC->hasAgg = 1;+
−
      }+
−
      if( is_agg ) pNC->allowAgg = 0;+
−
      for(i=0; pNC->nErr==0 && i<n; i++){+
−
        walkExprTree(pList->a[i].pExpr, nameResolverStep, pNC);+
−
      }+
−
      if( is_agg ) pNC->allowAgg = 1;+
−
      /* FIX ME:  Compute pExpr->affinity based on the expected return+
−
      ** type of the function +
−
      */+
−
      return is_agg;+
−
    }+
−
#ifndef SQLITE_OMIT_SUBQUERY+
−
    case TK_SELECT:+
−
    case TK_EXISTS:+
−
#endif+
−
    case TK_IN: {+
−
      if( pExpr->pSelect ){+
−
        int nRef = pNC->nRef;+
−
#ifndef SQLITE_OMIT_CHECK+
−
        if( pNC->isCheck ){+
−
          sqlite3ErrorMsg(pParse,"subqueries prohibited in CHECK constraints");+
−
        }+
−
#endif+
−
        sqlite3SelectResolve(pParse, pExpr->pSelect, pNC);+
−
        assert( pNC->nRef>=nRef );+
−
        if( nRef!=pNC->nRef ){+
−
          ExprSetProperty(pExpr, EP_VarSelect);+
−
        }+
−
      }+
−
      break;+
−
    }+
−
#ifndef SQLITE_OMIT_CHECK+
−
    case TK_VARIABLE: {+
−
      if( pNC->isCheck ){+
−
        sqlite3ErrorMsg(pParse,"parameters prohibited in CHECK constraints");+
−
      }+
−
      break;+
−
    }+
−
#endif+
−
  }+
−
  return 0;+
−
}+
−
+
−
/*+
−
** This routine walks an expression tree and resolves references to+
−
** table columns.  Nodes of the form ID.ID or ID resolve into an+
−
** index to the table in the table list and a column offset.  The +
−
** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable+
−
** value is changed to the index of the referenced table in pTabList+
−
** plus the "base" value.  The base value will ultimately become the+
−
** VDBE cursor number for a cursor that is pointing into the referenced+
−
** table.  The Expr.iColumn value is changed to the index of the column +
−
** of the referenced table.  The Expr.iColumn value for the special+
−
** ROWID column is -1.  Any INTEGER PRIMARY KEY column is tried as an+
−
** alias for ROWID.+
−
**+
−
** Also resolve function names and check the functions for proper+
−
** usage.  Make sure all function names are recognized and all functions+
−
** have the correct number of arguments.  Leave an error message+
−
** in pParse->zErrMsg if anything is amiss.  Return the number of errors.+
−
**+
−
** If the expression contains aggregate functions then set the EP_Agg+
−
** property on the expression.+
−
*/+
−
int sqlite3ExprResolveNames( +
−
  NameContext *pNC,       /* Namespace to resolve expressions in. */+
−
  Expr *pExpr             /* The expression to be analyzed. */+
−
){+
−
  int savedHasAgg;+
−
  if( pExpr==0 ) return 0;+
−
#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0+
−
  if( (pExpr->nHeight+pNC->pParse->nHeight)>SQLITE_MAX_EXPR_DEPTH ){+
−
    sqlite3ErrorMsg(pNC->pParse, +
−
       "Expression tree is too large (maximum depth %d)",+
−
       SQLITE_MAX_EXPR_DEPTH+
−
    );+
−
    return 1;+
−
  }+
−
  pNC->pParse->nHeight += pExpr->nHeight;+
−
#endif+
−
  savedHasAgg = pNC->hasAgg;+
−
  pNC->hasAgg = 0;+
−
  walkExprTree(pExpr, nameResolverStep, pNC);+
−
#if defined(SQLITE_TEST) || SQLITE_MAX_EXPR_DEPTH>0+
−
  pNC->pParse->nHeight -= pExpr->nHeight;+
−
#endif+
−
  if( pNC->nErr>0 ){+
−
    ExprSetProperty(pExpr, EP_Error);+
−
  }+
−
  if( pNC->hasAgg ){+
−
    ExprSetProperty(pExpr, EP_Agg);+
−
  }else if( savedHasAgg ){+
−
    pNC->hasAgg = 1;+
−
  }+
−
  return ExprHasProperty(pExpr, EP_Error);+
−
}+
−
+
−
/*+
−
** A pointer instance of this structure is used to pass information+
−
** through walkExprTree into codeSubqueryStep().+
−
*/+
−
typedef struct QueryCoder QueryCoder;+
−
struct QueryCoder {+
−
  Parse *pParse;       /* The parsing context */+
−
  NameContext *pNC;    /* Namespace of first enclosing query */+
−
};+
−
+
−
#ifdef SQLITE_TEST+
−
  int sqlite3_enable_in_opt = 1;+
−
#else+
−
  #define sqlite3_enable_in_opt 1+
−
#endif+
−
+
−
/*+
−
** This function is used by the implementation of the IN (...) operator.+
−
** It's job is to find or create a b-tree structure that may be used+
−
** either to test for membership of the (...) set or to iterate through+
−
** its members, skipping duplicates.+
−
**+
−
** The cursor opened on the structure (database table, database index +
−
** or ephermal table) is stored in pX->iTable before this function returns.+
−
** The returned value indicates the structure type, as follows:+
−
**+
−
**   IN_INDEX_ROWID - The cursor was opened on a database table.+
−
**   IN_INDEX_INDEX - The cursor was opened on a database indec.+
−
**   IN_INDEX_EPH -   The cursor was opened on a specially created and+
−
**                    populated epheremal table.+
−
**+
−
** An existing structure may only be used if the SELECT is of the simple+
−
** form:+
−
**+
−
**     SELECT <column> FROM <table>+
−
**+
−
** If the mustBeUnique parameter is false, the structure will be used +
−
** for fast set membership tests. In this case an epheremal table must +
−
** be used unless <column> is an INTEGER PRIMARY KEY or an index can +
−
** be found with <column> as its left-most column.+
−
**+
−
** If mustBeUnique is true, then the structure will be used to iterate+
−
** through the set members, skipping any duplicates. In this case an+
−
** epheremal table must be used unless the selected <column> is guaranteed+
−
** to be unique - either because it is an INTEGER PRIMARY KEY or it+
−
** is unique by virtue of a constraint or implicit index.+
−
*/+
−
#ifndef SQLITE_OMIT_SUBQUERY+
−
int sqlite3FindInIndex(Parse *pParse, Expr *pX, int mustBeUnique){+
−
  Select *p;+
−
  int eType = 0;+
−
  int iTab = pParse->nTab++;+
−
+
−
  /* The follwing if(...) expression is true if the SELECT is of the +
−
  ** simple form:+
−
  **+
−
  **     SELECT <column> FROM <table>+
−
  **+
−
  ** If this is the case, it may be possible to use an existing table+
−
  ** or index instead of generating an epheremal table.+
−
  */+
−
  if( sqlite3_enable_in_opt+
−
   && (p=pX->pSelect) && !p->pPrior+
−
   && !p->isDistinct && !p->isAgg && !p->pGroupBy+
−
   && p->pSrc && p->pSrc->nSrc==1 && !p->pSrc->a[0].pSelect+
−
   && !p->pSrc->a[0].pTab->pSelect                                  +
−
   && p->pEList->nExpr==1 && p->pEList->a[0].pExpr->op==TK_COLUMN+
−
   && !p->pLimit && !p->pOffset && !p->pWhere+
−
  ){+
−
    sqlite3 *db = pParse->db;+
−
    Index *pIdx;+
−
    Expr *pExpr = p->pEList->a[0].pExpr;+
−
    int iCol = pExpr->iColumn;+
−
    Vdbe *v = sqlite3GetVdbe(pParse);+
−
+
−
    /* This function is only called from two places. In both cases the vdbe+
−
    ** has already been allocated. So assume sqlite3GetVdbe() is always+
−
    ** successful here.+
−
    */+
−
    assert(v);+
−
    if( iCol<0 ){+
−
      int iMem = pParse->nMem++;+
−
      int iAddr;+
−
      Table *pTab = p->pSrc->a[0].pTab;+
−
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);+
−
      sqlite3VdbeUsesBtree(v, iDb);+
−
+
−
      sqlite3VdbeAddOp(v, OP_MemLoad, iMem, 0);+
−
      iAddr = sqlite3VdbeAddOp(v, OP_If, 0, iMem);+
−
      sqlite3VdbeAddOp(v, OP_MemInt, 1, iMem);+
−
+
−
      sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);+
−
      eType = IN_INDEX_ROWID;+
−
+
−
      sqlite3VdbeJumpHere(v, iAddr);+
−
    }else{+
−
      /* The collation sequence used by the comparison. If an index is to +
−
      ** be used in place of a temp-table, it must be ordered according+
−
      ** to this collation sequence.+
−
      */+
−
      CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);+
−
+
−
      /* Check that the affinity that will be used to perform the +
−
      ** comparison is the same as the affinity of the column. If+
−
      ** it is not, it is not possible to use any index.+
−
      */+
−
      Table *pTab = p->pSrc->a[0].pTab;+
−
      char aff = comparisonAffinity(pX);+
−
      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);+
−
+
−
      for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){+
−
        if( (pIdx->aiColumn[0]==iCol)+
−
         && (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))+
−
         && (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))+
−
        ){+
−
          int iDb;+
−
          int iMem = pParse->nMem++;+
−
          int iAddr;+
−
          char *pKey;+
−
  +
−
          pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);+
−
          iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);+
−
          sqlite3VdbeUsesBtree(v, iDb);+
−
+
−
          sqlite3VdbeAddOp(v, OP_MemLoad, iMem, 0);+
−
          iAddr = sqlite3VdbeAddOp(v, OP_If, 0, iMem);+
−
          sqlite3VdbeAddOp(v, OP_MemInt, 1, iMem);+
−
  +
−
          sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);+
−
          VdbeComment((v, "# %s", pIdx->zName));+
−
          sqlite3VdbeOp3(v,OP_OpenRead,iTab,pIdx->tnum,pKey,P3_KEYINFO_HANDOFF);+
−
          eType = IN_INDEX_INDEX;+
−
          sqlite3VdbeAddOp(v, OP_SetNumColumns, iTab, pIdx->nColumn);+
−
+
−
          sqlite3VdbeJumpHere(v, iAddr);+
−
        }+
−
      }+
−
    }+
−
  }+
−
+
−
  if( eType==0 ){+
−
    sqlite3CodeSubselect(pParse, pX);+
−
    eType = IN_INDEX_EPH;+
−
  }else{+
−
    pX->iTable = iTab;+
−
  }+
−
  return eType;+
−
}+
−
#endif+
−
+
−
/*+
−
** Generate code for scalar subqueries used as an expression+
−
** and IN operators.  Examples:+
−
**+
−
**     (SELECT a FROM b)          -- subquery+
−
**     EXISTS (SELECT a FROM b)   -- EXISTS subquery+
−
**     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 describes the expression that contains the IN+
−
** operator or subquery.+
−
*/+
−
#ifndef SQLITE_OMIT_SUBQUERY+
−
void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){+
−
  int testAddr = 0;                       /* One-time test address */+
−
  Vdbe *v = sqlite3GetVdbe(pParse);+
−
  if( v==0 ) return;+
−
+
−
+
−
  /* This code must be run in its entirety 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( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){+
−
    int mem = pParse->nMem++;+
−
    sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0);+
−
    testAddr = sqlite3VdbeAddOp(v, OP_If, 0, 0);+
−
    assert( testAddr>0 || pParse->db->mallocFailed );+
−
    sqlite3VdbeAddOp(v, OP_MemInt, 1, mem);+
−
  }+
−
+
−
  switch( pExpr->op ){+
−
    case TK_IN: {+
−
      char affinity;+
−
      KeyInfo keyInfo;+
−
      int addr;        /* Address of OP_OpenEphemeral instruction */+
−
+
−
      affinity = sqlite3ExprAffinity(pExpr->pLeft);+
−
+
−
      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'+
−
      ** expression it is handled the same way. A virtual table is +
−
      ** filled with single-field index keys representing the results+
−
      ** from the SELECT or the <exprlist>.+
−
      **+
−
      ** If the 'x' expression 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.+
−
      */+
−
      pExpr->iTable = pParse->nTab++;+
−
      addr = sqlite3VdbeAddOp(v, OP_OpenEphemeral, pExpr->iTable, 0);+
−
      memset(&keyInfo, 0, sizeof(keyInfo));+
−
      keyInfo.nField = 1;+
−
      sqlite3VdbeAddOp(v, OP_SetNumColumns, pExpr->iTable, 1);+
−
+
−
      if( pExpr->pSelect ){+
−
        /* Case 1:     expr IN (SELECT ...)+
−
        **+
−
        ** Generate code to write the results of the select into the temporary+
−
        ** table allocated and opened above.+
−
        */+
−
        int iParm = pExpr->iTable +  (((int)affinity)<<16);+
−
        ExprList *pEList;+
−
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );+
−
        if( sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0) ){+
−
          return;+
−
        }+
−
        pEList = pExpr->pSelect->pEList;+
−
        if( pEList && pEList->nExpr>0 ){ +
−
          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,+
−
              pEList->a[0].pExpr);+
−
        }+
−
      }else if( pExpr->pList ){+
−
        /* Case 2:     expr IN (exprlist)+
−
        **+
−
        ** For each expression, build an index key from the evaluation and+
−
        ** store it in the temporary table. If <expr> is a column, then use+
−
        ** that columns affinity when building index keys. If <expr> is not+
−
        ** a column, use numeric affinity.+
−
        */+
−
        int i;+
−
        ExprList *pList = pExpr->pList;+
−
		ExprList::ExprList_item *pItem;+
−
+
−
        if( !affinity ){+
−
          affinity = SQLITE_AFF_NONE;+
−
        }+
−
        keyInfo.aColl[0] = pExpr->pLeft->pColl;+
−
+
−
        /* Loop through each expression in <exprlist>. */+
−
        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){+
−
          Expr *pE2 = pItem->pExpr;+
−
+
−
          /* If the expression is not constant then we will need to+
−
          ** disable the test that was generated above that makes sure+
−
          ** this code only executes once.  Because for a non-constant+
−
          ** expression we need to rerun this code each time.+
−
          */+
−
          if( testAddr>0 && !sqlite3ExprIsConstant(pE2) ){+
−
            sqlite3VdbeChangeToNoop(v, testAddr-1, 3);+
−
            testAddr = 0;+
−
          }+
−
+
−
          /* Evaluate the expression and insert it into the temp table */+
−
          sqlite3ExprCode(pParse, pE2);+
−
          sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);+
−
          sqlite3VdbeAddOp(v, OP_IdxInsert, pExpr->iTable, 0);+
−
        }+
−
      }+
−
      sqlite3VdbeChangeP3(v, addr, (const char *)&keyInfo, P3_KEYINFO);+
−
      break;+
−
    }+
−
+
−
    case TK_EXISTS:+
−
    case TK_SELECT: {+
−
      /* This has to be a scalar SELECT.  Generate code to put the+
−
      ** value of this select in a memory cell and record the number+
−
      ** of the memory cell in iColumn.+
−
      */+
−
      static const Token one = { (u8*)"1", 0, 1 };+
−
      Select *pSel;+
−
      int iMem;+
−
      int sop;+
−
+
−
      pExpr->iColumn = iMem = pParse->nMem++;+
−
      pSel = pExpr->pSelect;+
−
      if( pExpr->op==TK_SELECT ){+
−
        sop = SRT_Mem;+
−
        sqlite3VdbeAddOp(v, OP_MemNull, iMem, 0);+
−
        VdbeComment((v, "# Init subquery result"));+
−
      }else{+
−
        sop = SRT_Exists;+
−
        sqlite3VdbeAddOp(v, OP_MemInt, 0, iMem);+
−
        VdbeComment((v, "# Init EXISTS result"));+
−
      }+
−
      sqlite3ExprDelete(pSel->pLimit);+
−
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);+
−
      if( sqlite3Select(pParse, pSel, sop, iMem, 0, 0, 0, 0) ){+
−
        return;+
−
      }+
−
      break;+
−
    }+
−
  }+
−
+
−
  if( testAddr ){+
−
    sqlite3VdbeJumpHere(v, testAddr);+
−
  }+
−
+
−
  return;+
−
}+
−
#endif /* SQLITE_OMIT_SUBQUERY */+
−
+
−
/*+
−
** Duplicate an 8-byte value+
−
*/+
−
static char *dup8bytes(Vdbe *v, const char *in){+
−
  char *out = (char*)sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);+
−
  if( out ){+
−
    memcpy(out, in, 8);+
−
  }+
−
  return out;+
−
}+
−
+
−
/*+
−
** Generate an instruction that will put the floating point+
−
** value described by z[0..n-1] on the stack.+
−
**+
−
** The z[] string will probably not be zero-terminated.  But the +
−
** z[n] character is guaranteed to be something that does not look+
−
** like the continuation of the number.+
−
*/+
−
static void codeReal(Vdbe *v, const char *z, int n, int negateFlag){+
−
  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );+
−
  if( z ){+
−
    double value;+
−
    char *zV;+
−
    assert( !isdigit(z[n]) );+
−
    sqlite3AtoF(z, &value);+
−
    if( negateFlag ) value = -value;+
−
    zV = dup8bytes(v, (char*)&value);+
−
    sqlite3VdbeOp3(v, OP_Real, 0, 0, zV, P3_REAL);+
−
  }+
−
}+
−
+
−
+
−
/*+
−
** Generate an instruction that will put the integer describe by+
−
** text z[0..n-1] on the stack.+
−
**+
−
** The z[] string will probably not be zero-terminated.  But the +
−
** z[n] character is guaranteed to be something that does not look+
−
** like the continuation of the number.+
−
*/+
−
static void codeInteger(Vdbe *v, const char *z, int n, int negateFlag){+
−
  assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );+
−
  if( z ){+
−
    int i;+
−
    assert( !isdigit(z[n]) );+
−
    if( sqlite3GetInt32(z, &i) ){+
−
      if( negateFlag ) i = -i;+
−
      sqlite3VdbeAddOp(v, OP_Integer, i, 0);+
−
    }else if( sqlite3FitsIn64Bits(z, negateFlag) ){+
−
      i64 value;+
−
      char *zV;+
−
      sqlite3Atoi64(z, &value);+
−
      if( negateFlag ) value = -value;+
−
      zV = dup8bytes(v, (char*)&value);+
−
      sqlite3VdbeOp3(v, OP_Int64, 0, 0, zV, P3_INT64);+
−
    }else{+
−
      codeReal(v, z, n, negateFlag);+
−
    }+
−
  }+
−
}+
−
+
−
+
−
/*+
−
** Generate code that will extract the iColumn-th column from+
−
** table pTab and push that column value on the stack.  There+
−
** is an open cursor to pTab in iTable.  If iColumn<0 then+
−
** code is generated that extracts the rowid.+
−
*/+
−
void sqlite3ExprCodeGetColumn(Vdbe *v, Table *pTab, int iColumn, int iTable){+
−
  if( iColumn<0 ){+
−
    int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;+
−
    sqlite3VdbeAddOp(v, op, iTable, 0);+
−
  }else if( pTab==0 ){+
−
    sqlite3VdbeAddOp(v, OP_Column, iTable, iColumn);+
−
  }else{+
−
    int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;+
−
    sqlite3VdbeAddOp(v, op, iTable, iColumn);+
−
    sqlite3ColumnDefault(v, pTab, iColumn);+
−
#ifndef SQLITE_OMIT_FLOATING_POINT+
−
    if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){+
−
      sqlite3VdbeAddOp(v, OP_RealAffinity, 0, 0);+
−
    }+
−
#endif+
−
  }+
−
}+
−
+
−
/*+
−
** Generate code into the current Vdbe to evaluate the given+
−
** expression and leave the result on the top of stack.+
−
**+
−
** This code depends on the fact that certain token values (ex: TK_EQ)+
−
** are the same as opcode values (ex: OP_Eq) that implement the corresponding+
−
** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in+
−
** the make process cause these values to align.  Assert()s in the code+
−
** below verify that the numbers are aligned correctly.+
−
*/+
−
void sqlite3ExprCode(Parse *pParse, Expr *pExpr){+
−
  Vdbe *v = pParse->pVdbe;+
−
  int op;+
−
  int stackChng = 1;    /* Amount of change to stack depth */+
−
+
−
  if( v==0 ) return;+
−
  if( pExpr==0 ){+
−
    sqlite3VdbeAddOp(v, OP_Null, 0, 0);+
−
    return;+
−
  }+
−
  op = pExpr->op;+
−
  switch( op ){+
−
    case TK_AGG_COLUMN: {+
−
      AggInfo *pAggInfo = pExpr->pAggInfo;+
−
	  AggInfo::AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];+
−
      if( !pAggInfo->directMode ){+
−
        sqlite3VdbeAddOp(v, OP_MemLoad, pCol->iMem, 0);+
−
        break;+
−
      }else if( pAggInfo->useSortingIdx ){+
−
        sqlite3VdbeAddOp(v, OP_Column, pAggInfo->sortingIdx,+
−
                              pCol->iSorterColumn);+
−
        break;+
−
      }+
−
      /* Otherwise, fall thru into the TK_COLUMN case */+
−
    }+
−
    case TK_COLUMN: {+
−
      if( pExpr->iTable<0 ){+
−
        /* This only happens when coding check constraints */+
−
        assert( pParse->ckOffset>0 );+
−
        sqlite3VdbeAddOp(v, OP_Dup, pParse->ckOffset-pExpr->iColumn-1, 1);+
−
      }else{+
−
        sqlite3ExprCodeGetColumn(v, pExpr->pTab, pExpr->iColumn, pExpr->iTable);+
−
      }+
−
      break;+
−
    }+
−
    case TK_INTEGER: {+
−
      codeInteger(v, (char*)pExpr->token.z, pExpr->token.n, 0);+
−
      break;+
−
    }+
−
    case TK_FLOAT: {+
−
      codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0);+
−
      break;+
−
    }+
−
    case TK_STRING: {+
−
      sqlite3DequoteExpr(pParse->db, pExpr);+
−
      sqlite3VdbeOp3(v,OP_String8, 0, 0, (char*)pExpr->token.z, pExpr->token.n);+
−
      break;+
−
    }+
−
    case TK_NULL: {+
−
      sqlite3VdbeAddOp(v, OP_Null, 0, 0);+
−
      break;+
−
    }+
−
#ifndef SQLITE_OMIT_BLOB_LITERAL+
−
    case TK_BLOB: {+
−
      int n;+
−
      const char *z;+
−
      assert( TK_BLOB==OP_HexBlob );+
−
      n = pExpr->token.n - 3;+
−
      z = (char*)pExpr->token.z + 2;+
−
      assert( n>=0 );+
−
      if( n==0 ){+
−
        z = "";+
−
      }+
−
      sqlite3VdbeOp3(v, op, 0, 0, z, n);+
−
      break;+
−
    }+
−
#endif+
−
    case TK_VARIABLE: {+
−
      sqlite3VdbeAddOp(v, OP_Variable, pExpr->iTable, 0);+
−
      if( pExpr->token.n>1 ){+
−
        sqlite3VdbeChangeP3(v, -1, (char*)pExpr->token.z, pExpr->token.n);+
−
      }+
−
      break;+
−
    }+
−
    case TK_REGISTER: {+
−
      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iTable, 0);+
−
      break;+
−
    }+
−
#ifndef SQLITE_OMIT_CAST+
−
    case TK_CAST: {+
−
      /* Expressions of the form:   CAST(pLeft AS token) */+
−
      int aff, to_op;+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      aff = sqlite3AffinityType(&pExpr->token);+
−
      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;+
−
      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );+
−
      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );+
−
      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );+
−
      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );+
−
      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );+
−
      sqlite3VdbeAddOp(v, to_op, 0, 0);+
−
      stackChng = 0;+
−
      break;+
−
    }+
−
#endif /* SQLITE_OMIT_CAST */+
−
    case TK_LT:+
−
    case TK_LE:+
−
    case TK_GT:+
−
    case TK_GE:+
−
    case TK_NE:+
−
    case TK_EQ: {+
−
      assert( TK_LT==OP_Lt );+
−
      assert( TK_LE==OP_Le );+
−
      assert( TK_GT==OP_Gt );+
−
      assert( TK_GE==OP_Ge );+
−
      assert( TK_EQ==OP_Eq );+
−
      assert( TK_NE==OP_Ne );+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3ExprCode(pParse, pExpr->pRight);+
−
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, 0, 0);+
−
      stackChng = -1;+
−
      break;+
−
    }+
−
    case TK_AND:+
−
    case TK_OR:+
−
    case TK_PLUS:+
−
    case TK_STAR:+
−
    case TK_MINUS:+
−
    case TK_REM:+
−
    case TK_BITAND:+
−
    case TK_BITOR:+
−
    case TK_SLASH:+
−
    case TK_LSHIFT:+
−
    case TK_RSHIFT: +
−
    case TK_CONCAT: {+
−
      assert( TK_AND==OP_And );+
−
      assert( TK_OR==OP_Or );+
−
      assert( TK_PLUS==OP_Add );+
−
      assert( TK_MINUS==OP_Subtract );+
−
      assert( TK_REM==OP_Remainder );+
−
      assert( TK_BITAND==OP_BitAnd );+
−
      assert( TK_BITOR==OP_BitOr );+
−
      assert( TK_SLASH==OP_Divide );+
−
      assert( TK_LSHIFT==OP_ShiftLeft );+
−
      assert( TK_RSHIFT==OP_ShiftRight );+
−
      assert( TK_CONCAT==OP_Concat );+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3ExprCode(pParse, pExpr->pRight);+
−
      sqlite3VdbeAddOp(v, op, 0, 0);+
−
      stackChng = -1;+
−
      break;+
−
    }+
−
    case TK_UMINUS: {+
−
      Expr *pLeft = pExpr->pLeft;+
−
      assert( pLeft );+
−
      if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){+
−
        Token *p = &pLeft->token;+
−
        if( pLeft->op==TK_FLOAT ){+
−
          codeReal(v, (char*)p->z, p->n, 1);+
−
        }else{+
−
          codeInteger(v, (char*)p->z, p->n, 1);+
−
        }+
−
        break;+
−
      }+
−
      /* Fall through into TK_NOT */+
−
    }+
−
    case TK_BITNOT:+
−
    case TK_NOT: {+
−
      assert( TK_BITNOT==OP_BitNot );+
−
      assert( TK_NOT==OP_Not );+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3VdbeAddOp(v, op, 0, 0);+
−
      stackChng = 0;+
−
      break;+
−
    }+
−
    case TK_ISNULL:+
−
    case TK_NOTNULL: {+
−
      int dest;+
−
      assert( TK_ISNULL==OP_IsNull );+
−
      assert( TK_NOTNULL==OP_NotNull );+
−
      sqlite3VdbeAddOp(v, OP_Integer, 1, 0);+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      dest = sqlite3VdbeCurrentAddr(v) + 2;+
−
      sqlite3VdbeAddOp(v, op, 1, dest);+
−
      sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);+
−
      stackChng = 0;+
−
      break;+
−
    }+
−
    case TK_AGG_FUNCTION: {+
−
      AggInfo *pInfo = pExpr->pAggInfo;+
−
      if( pInfo==0 ){+
−
        sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",+
−
            &pExpr->span);+
−
      }else{+
−
        sqlite3VdbeAddOp(v, OP_MemLoad, pInfo->aFunc[pExpr->iAgg].iMem, 0);+
−
      }+
−
      break;+
−
    }+
−
    case TK_CONST_FUNC:+
−
    case TK_FUNCTION: {+
−
      ExprList *pList = pExpr->pList;+
−
      int nExpr = pList ? pList->nExpr : 0;+
−
      FuncDef *pDef;+
−
      int nId;+
−
      const char *zId;+
−
      int constMask = 0;+
−
      int i;+
−
      sqlite3 *db = pParse->db;+
−
      u8 enc = ENC(db);+
−
      CollSeq *pColl = 0;+
−
+
−
      zId = (char*)pExpr->token.z;+
−
      nId = pExpr->token.n;+
−
      pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);+
−
      assert( pDef!=0 );+
−
      nExpr = sqlite3ExprCodeExprList(pParse, pList);+
−
#ifndef SQLITE_OMIT_VIRTUALTABLE+
−
      /* Possibly overload the function if the first argument is+
−
      ** a virtual table column.+
−
      **+
−
      ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the+
−
      ** second argument, not the first, as the argument to test to+
−
      ** see if it is a column in a virtual table.  This is done because+
−
      ** the left operand of infix functions (the operand we want to+
−
      ** control overloading) ends up as the second argument to the+
−
      ** function.  The expression "A glob B" is equivalent to +
−
      ** "glob(B,A).  We want to use the A in "A glob B" to test+
−
      ** for function overloading.  But we use the B term in "glob(B,A)".+
−
      */+
−
      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){+
−
        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);+
−
      }else if( nExpr>0 ){+
−
        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);+
−
      }+
−
#endif+
−
      for(i=0; i<nExpr && i<32; i++){+
−
        if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){+
−
          constMask |= (1<<i);+
−
        }+
−
        if( pDef->needCollSeq && !pColl ){+
−
          pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);+
−
        }+
−
      }+
−
      if( pDef->needCollSeq ){+
−
        if( !pColl ) pColl = pParse->db->pDfltColl; +
−
        sqlite3VdbeOp3(v, OP_CollSeq, 0, 0, (char *)pColl, P3_COLLSEQ);+
−
      }+
−
      sqlite3VdbeOp3(v, OP_Function, constMask, nExpr, (char*)pDef, P3_FUNCDEF);+
−
      stackChng = 1-nExpr;+
−
      break;+
−
    }+
−
#ifndef SQLITE_OMIT_SUBQUERY+
−
    case TK_EXISTS:+
−
    case TK_SELECT: {+
−
      if( pExpr->iColumn==0 ){+
−
        sqlite3CodeSubselect(pParse, pExpr);+
−
      }+
−
      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);+
−
      VdbeComment((v, "# load subquery result"));+
−
      break;+
−
    }+
−
    case TK_IN: {+
−
      int addr;+
−
      char affinity;+
−
      int ckOffset = pParse->ckOffset;+
−
      int eType;+
−
      int iLabel = sqlite3VdbeMakeLabel(v);+
−
+
−
      eType = sqlite3FindInIndex(pParse, pExpr, 0);+
−
+
−
      /* Figure out the affinity to use to create a key from the results+
−
      ** of the expression. affinityStr stores a static string suitable for+
−
      ** P3 of OP_MakeRecord.+
−
      */+
−
      affinity = comparisonAffinity(pExpr);+
−
+
−
      sqlite3VdbeAddOp(v, OP_Integer, 1, 0);+
−
      pParse->ckOffset = (ckOffset ? (ckOffset+1) : 0);+
−
+
−
      /* Code the <expr> from "<expr> IN (...)". The temporary table+
−
      ** pExpr->iTable contains the values that make up the (...) set.+
−
      */+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      addr = sqlite3VdbeCurrentAddr(v);+
−
      sqlite3VdbeAddOp(v, OP_NotNull, -1, addr+4);            /* addr + 0 */+
−
      sqlite3VdbeAddOp(v, OP_Pop, 2, 0);+
−
      sqlite3VdbeAddOp(v, OP_Null, 0, 0);+
−
      sqlite3VdbeAddOp(v, OP_Goto, 0, iLabel);+
−
      if( eType==IN_INDEX_ROWID ){+
−
        int iAddr = sqlite3VdbeCurrentAddr(v)+3;+
−
        sqlite3VdbeAddOp(v, OP_MustBeInt, 1, iAddr);+
−
        sqlite3VdbeAddOp(v, OP_NotExists, pExpr->iTable, iAddr);+
−
        sqlite3VdbeAddOp(v, OP_Goto, pExpr->iTable, iLabel);+
−
      }else{+
−
        sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);   /* addr + 4 */+
−
        sqlite3VdbeAddOp(v, OP_Found, pExpr->iTable, iLabel);+
−
      }+
−
      sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);                  /* addr + 6 */+
−
      sqlite3VdbeResolveLabel(v, iLabel);+
−
+
−
      break;+
−
    }+
−
#endif+
−
    case TK_BETWEEN: {+
−
      Expr *pLeft = pExpr->pLeft;+
−
	  ExprList::ExprList_item *pLItem = pExpr->pList->a;+
−
      Expr *pRight = pLItem->pExpr;+
−
      sqlite3ExprCode(pParse, pLeft);+
−
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);+
−
      sqlite3ExprCode(pParse, pRight);+
−
      codeCompare(pParse, pLeft, pRight, OP_Ge, 0, 0);+
−
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);+
−
      pLItem++;+
−
      pRight = pLItem->pExpr;+
−
      sqlite3ExprCode(pParse, pRight);+
−
      codeCompare(pParse, pLeft, pRight, OP_Le, 0, 0);+
−
      sqlite3VdbeAddOp(v, OP_And, 0, 0);+
−
      break;+
−
    }+
−
    case TK_UPLUS: {+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      stackChng = 0;+
−
      break;+
−
    }+
−
    case TK_CASE: {+
−
      int expr_end_label;+
−
      int jumpInst;+
−
      int nExpr;+
−
      int i;+
−
      ExprList *pEList;+
−
	  ExprList::ExprList_item *aListelem;+
−
+
−
      assert(pExpr->pList);+
−
      assert((pExpr->pList->nExpr % 2) == 0);+
−
      assert(pExpr->pList->nExpr > 0);+
−
      pEList = pExpr->pList;+
−
      aListelem = pEList->a;+
−
      nExpr = pEList->nExpr;+
−
      expr_end_label = sqlite3VdbeMakeLabel(v);+
−
      if( pExpr->pLeft ){+
−
        sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      }+
−
      for(i=0; i<nExpr; i=i+2){+
−
        sqlite3ExprCode(pParse, aListelem[i].pExpr);+
−
        if( pExpr->pLeft ){+
−
          sqlite3VdbeAddOp(v, OP_Dup, 1, 1);+
−
          jumpInst = codeCompare(pParse, pExpr->pLeft, aListelem[i].pExpr,+
−
                                 OP_Ne, 0, 1);+
−
          sqlite3VdbeAddOp(v, OP_Pop, 1, 0);+
−
        }else{+
−
          jumpInst = sqlite3VdbeAddOp(v, OP_IfNot, 1, 0);+
−
        }+
−
        sqlite3ExprCode(pParse, aListelem[i+1].pExpr);+
−
        sqlite3VdbeAddOp(v, OP_Goto, 0, expr_end_label);+
−
        sqlite3VdbeJumpHere(v, jumpInst);+
−
      }+
−
      if( pExpr->pLeft ){+
−
        sqlite3VdbeAddOp(v, OP_Pop, 1, 0);+
−
      }+
−
      if( pExpr->pRight ){+
−
        sqlite3ExprCode(pParse, pExpr->pRight);+
−
      }else{+
−
        sqlite3VdbeAddOp(v, OP_Null, 0, 0);+
−
      }+
−
      sqlite3VdbeResolveLabel(v, expr_end_label);+
−
      break;+
−
    }+
−
#ifndef SQLITE_OMIT_TRIGGER+
−
    case TK_RAISE: {+
−
      if( !pParse->trigStack ){+
−
        sqlite3ErrorMsg(pParse,+
−
                       "RAISE() may only be used within a trigger-program");+
−
        return;+
−
      }+
−
      if( pExpr->iColumn!=OE_Ignore ){+
−
         assert( pExpr->iColumn==OE_Rollback ||+
−
                 pExpr->iColumn == OE_Abort ||+
−
                 pExpr->iColumn == OE_Fail );+
−
         sqlite3DequoteExpr(pParse->db, pExpr);+
−
         sqlite3VdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn,+
−
                        (char*)pExpr->token.z, pExpr->token.n);+
−
      } else {+
−
         assert( pExpr->iColumn == OE_Ignore );+
−
         sqlite3VdbeAddOp(v, OP_ContextPop, 0, 0);+
−
         sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->trigStack->ignoreJump);+
−
         VdbeComment((v, "# raise(IGNORE)"));+
−
      }+
−
      stackChng = 0;+
−
      break;+
−
    }+
−
#endif+
−
  }+
−
+
−
  if( pParse->ckOffset ){+
−
    pParse->ckOffset += stackChng;+
−
    assert( pParse->ckOffset );+
−
  }+
−
}+
−
+
−
#ifndef SQLITE_OMIT_TRIGGER+
−
/*+
−
** Generate code that evalutes the given expression and leaves the result+
−
** on the stack.  See also sqlite3ExprCode().+
−
**+
−
** This routine might also cache the result and modify the pExpr tree+
−
** so that it will make use of the cached result on subsequent evaluations+
−
** rather than evaluate the whole expression again.  Trivial expressions are+
−
** not cached.  If the expression is cached, its result is stored in a +
−
** memory location.+
−
*/+
−
void sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr){+
−
  Vdbe *v = pParse->pVdbe;+
−
  VdbeOp *pOp;+
−
  int iMem;+
−
  int addr1, addr2;+
−
  if( v==0 ) return;+
−
  addr1 = sqlite3VdbeCurrentAddr(v);+
−
  sqlite3ExprCode(pParse, pExpr);+
−
  addr2 = sqlite3VdbeCurrentAddr(v);+
−
  if( addr2>addr1+1+
−
   || ((pOp = sqlite3VdbeGetOp(v, addr1))!=0 && pOp->opcode==OP_Function) ){+
−
    iMem = pExpr->iTable = pParse->nMem++;+
−
    sqlite3VdbeAddOp(v, OP_MemStore, iMem, 0);+
−
    pExpr->op = TK_REGISTER;+
−
  }+
−
}+
−
#endif+
−
+
−
/*+
−
** Generate code that pushes the value of every element of the given+
−
** expression list onto the stack.+
−
**+
−
** Return the number of elements pushed onto the stack.+
−
*/+
−
int sqlite3ExprCodeExprList(+
−
  Parse *pParse,     /* Parsing context */+
−
  ExprList *pList    /* The expression list to be coded */+
−
){+
−
	ExprList::ExprList_item *pItem;+
−
  int i, n;+
−
  if( pList==0 ) return 0;+
−
  n = pList->nExpr;+
−
  for(pItem=pList->a, i=n; i>0; i--, pItem++){+
−
    sqlite3ExprCode(pParse, pItem->pExpr);+
−
  }+
−
  return n;+
−
}+
−
+
−
/*+
−
** Generate code for a boolean expression such that a jump is made+
−
** to the label "dest" if the expression is true but execution+
−
** continues straight thru if the expression is false.+
−
**+
−
** If the expression evaluates to NULL (neither true nor false), then+
−
** take the jump if the jumpIfNull flag is true.+
−
**+
−
** This code depends on the fact that certain token values (ex: TK_EQ)+
−
** are the same as opcode values (ex: OP_Eq) that implement the corresponding+
−
** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in+
−
** the make process cause these values to align.  Assert()s in the code+
−
** below verify that the numbers are aligned correctly.+
−
*/+
−
void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){+
−
  Vdbe *v = pParse->pVdbe;+
−
  int op = 0;+
−
  int ckOffset = pParse->ckOffset;+
−
  if( v==0 || pExpr==0 ) return;+
−
  op = pExpr->op;+
−
  switch( op ){+
−
    case TK_AND: {+
−
      int d2 = sqlite3VdbeMakeLabel(v);+
−
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2, !jumpIfNull);+
−
      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);+
−
      sqlite3VdbeResolveLabel(v, d2);+
−
      break;+
−
    }+
−
    case TK_OR: {+
−
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);+
−
      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_NOT: {+
−
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_LT:+
−
    case TK_LE:+
−
    case TK_GT:+
−
    case TK_GE:+
−
    case TK_NE:+
−
    case TK_EQ: {+
−
      assert( TK_LT==OP_Lt );+
−
      assert( TK_LE==OP_Le );+
−
      assert( TK_GT==OP_Gt );+
−
      assert( TK_GE==OP_Ge );+
−
      assert( TK_EQ==OP_Eq );+
−
      assert( TK_NE==OP_Ne );+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3ExprCode(pParse, pExpr->pRight);+
−
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_ISNULL:+
−
    case TK_NOTNULL: {+
−
      assert( TK_ISNULL==OP_IsNull );+
−
      assert( TK_NOTNULL==OP_NotNull );+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3VdbeAddOp(v, op, 1, dest);+
−
      break;+
−
    }+
−
    case TK_BETWEEN: {+
−
      /* The expression "x BETWEEN y AND z" is implemented as:+
−
      **+
−
      ** 1 IF (x < y) GOTO 3+
−
      ** 2 IF (x <= z) GOTO <dest>+
−
      ** 3 ...+
−
      */+
−
      int addr;+
−
      Expr *pLeft = pExpr->pLeft;+
−
      Expr *pRight = pExpr->pList->a[0].pExpr;+
−
      sqlite3ExprCode(pParse, pLeft);+
−
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);+
−
      sqlite3ExprCode(pParse, pRight);+
−
      addr = codeCompare(pParse, pLeft, pRight, OP_Lt, 0, !jumpIfNull);+
−
+
−
      pRight = pExpr->pList->a[1].pExpr;+
−
      sqlite3ExprCode(pParse, pRight);+
−
      codeCompare(pParse, pLeft, pRight, OP_Le, dest, jumpIfNull);+
−
+
−
      sqlite3VdbeAddOp(v, OP_Integer, 0, 0);+
−
      sqlite3VdbeJumpHere(v, addr);+
−
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);+
−
      break;+
−
    }+
−
    default: {+
−
      sqlite3ExprCode(pParse, pExpr);+
−
      sqlite3VdbeAddOp(v, OP_If, jumpIfNull, dest);+
−
      break;+
−
    }+
−
  }+
−
  pParse->ckOffset = ckOffset;+
−
}+
−
+
−
/*+
−
** Generate code for a boolean expression such that a jump is made+
−
** to the label "dest" if the expression is false but execution+
−
** continues straight thru if the expression is true.+
−
**+
−
** If the expression evaluates to NULL (neither true nor false) then+
−
** jump if jumpIfNull is true or fall through if jumpIfNull is false.+
−
*/+
−
void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){+
−
  Vdbe *v = pParse->pVdbe;+
−
  int op = 0;+
−
  int ckOffset = pParse->ckOffset;+
−
  if( v==0 || pExpr==0 ) return;+
−
+
−
  /* The value of pExpr->op and op are related as follows:+
−
  **+
−
  **       pExpr->op            op+
−
  **       ---------          ----------+
−
  **       TK_ISNULL          OP_NotNull+
−
  **       TK_NOTNULL         OP_IsNull+
−
  **       TK_NE              OP_Eq+
−
  **       TK_EQ              OP_Ne+
−
  **       TK_GT              OP_Le+
−
  **       TK_LE              OP_Gt+
−
  **       TK_GE              OP_Lt+
−
  **       TK_LT              OP_Ge+
−
  **+
−
  ** For other values of pExpr->op, op is undefined and unused.+
−
  ** The value of TK_ and OP_ constants are arranged such that we+
−
  ** can compute the mapping above using the following expression.+
−
  ** Assert()s verify that the computation is correct.+
−
  */+
−
  op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);+
−
+
−
  /* Verify correct alignment of TK_ and OP_ constants+
−
  */+
−
  assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );+
−
  assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );+
−
  assert( pExpr->op!=TK_NE || op==OP_Eq );+
−
  assert( pExpr->op!=TK_EQ || op==OP_Ne );+
−
  assert( pExpr->op!=TK_LT || op==OP_Ge );+
−
  assert( pExpr->op!=TK_LE || op==OP_Gt );+
−
  assert( pExpr->op!=TK_GT || op==OP_Le );+
−
  assert( pExpr->op!=TK_GE || op==OP_Lt );+
−
+
−
  switch( pExpr->op ){+
−
    case TK_AND: {+
−
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);+
−
      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_OR: {+
−
      int d2 = sqlite3VdbeMakeLabel(v);+
−
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, !jumpIfNull);+
−
      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);+
−
      sqlite3VdbeResolveLabel(v, d2);+
−
      break;+
−
    }+
−
    case TK_NOT: {+
−
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_LT:+
−
    case TK_LE:+
−
    case TK_GT:+
−
    case TK_GE:+
−
    case TK_NE:+
−
    case TK_EQ: {+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3ExprCode(pParse, pExpr->pRight);+
−
      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    case TK_ISNULL:+
−
    case TK_NOTNULL: {+
−
      sqlite3ExprCode(pParse, pExpr->pLeft);+
−
      sqlite3VdbeAddOp(v, op, 1, dest);+
−
      break;+
−
    }+
−
    case TK_BETWEEN: {+
−
      /* The expression is "x BETWEEN y AND z". It is implemented as:+
−
      **+
−
      ** 1 IF (x >= y) GOTO 3+
−
      ** 2 GOTO <dest>+
−
      ** 3 IF (x > z) GOTO <dest>+
−
      */+
−
      int addr;+
−
      Expr *pLeft = pExpr->pLeft;+
−
      Expr *pRight = pExpr->pList->a[0].pExpr;+
−
      sqlite3ExprCode(pParse, pLeft);+
−
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);+
−
      sqlite3ExprCode(pParse, pRight);+
−
      addr = sqlite3VdbeCurrentAddr(v);+
−
      codeCompare(pParse, pLeft, pRight, OP_Ge, addr+3, !jumpIfNull);+
−
+
−
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);+
−
      sqlite3VdbeAddOp(v, OP_Goto, 0, dest);+
−
      pRight = pExpr->pList->a[1].pExpr;+
−
      sqlite3ExprCode(pParse, pRight);+
−
      codeCompare(pParse, pLeft, pRight, OP_Gt, dest, jumpIfNull);+
−
      break;+
−
    }+
−
    default: {+
−
      sqlite3ExprCode(pParse, pExpr);+
−
      sqlite3VdbeAddOp(v, OP_IfNot, jumpIfNull, dest);+
−
      break;+
−
    }+
−
  }+
−
  pParse->ckOffset = ckOffset;+
−
}+
−
+
−
/*+
−
** Do a deep comparison of two expression trees.  Return TRUE (non-zero)+
−
** if they are identical and return FALSE if they differ in any way.+
−
**+
−
** Sometimes this routine will return FALSE even if the two expressions+
−
** really are equivalent.  If we cannot prove that the expressions are+
−
** identical, we return FALSE just to be safe.  So if this routine+
−
** returns false, then you do not really know for certain if the two+
−
** expressions are the same.  But if you get a TRUE return, then you+
−
** can be sure the expressions are the same.  In the places where+
−
** this routine is used, it does not hurt to get an extra FALSE - that+
−
** just might result in some slightly slower code.  But returning+
−
** an incorrect TRUE could lead to a malfunction.+
−
*/+
−
int sqlite3ExprCompare(Expr *pA, Expr *pB){+
−
  int i;+
−
  if( pA==0||pB==0 ){+
−
    return pB==pA;+
−
  }+
−
  if( pA->op!=pB->op ) return 0;+
−
  if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0;+
−
  if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;+
−
  if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;+
−
  if( pA->pList ){+
−
    if( pB->pList==0 ) return 0;+
−
    if( pA->pList->nExpr!=pB->pList->nExpr ) return 0;+
−
    for(i=0; i<pA->pList->nExpr; i++){+
−
      if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){+
−
        return 0;+
−
      }+
−
    }+
−
  }else if( pB->pList ){+
−
    return 0;+
−
  }+
−
  if( pA->pSelect || pB->pSelect ) return 0;+
−
  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;+
−
  if( pA->op!=TK_COLUMN && pA->token.z ){+
−
    if( pB->token.z==0 ) return 0;+
−
    if( pB->token.n!=pA->token.n ) return 0;+
−
    if( sqlite3StrNICmp((char*)pA->token.z,(char*)pB->token.z,pB->token.n)!=0 ){+
−
      return 0;+
−
    }+
−
  }+
−
  return 1;+
−
}+
−
+
−
+
−
/*+
−
** Add a new element to the pAggInfo->aCol[] array.  Return the index of+
−
** the new element.  Return a negative number if malloc fails.+
−
*/+
−
static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){+
−
  int i;+
−
  pInfo->aCol = (AggInfo::AggInfo_col*)sqlite3ArrayAllocate(+
−
       db,+
−
       pInfo->aCol,+
−
       sizeof(pInfo->aCol[0]),+
−
       3,+
−
       &pInfo->nColumn,+
−
       &pInfo->nColumnAlloc,+
−
       &i+
−
  );+
−
  return i;+
−
}    +
−
+
−
/*+
−
** Add a new element to the pAggInfo->aFunc[] array.  Return the index of+
−
** the new element.  Return a negative number if malloc fails.+
−
*/+
−
static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){+
−
  int i;+
−
  pInfo->aFunc = (AggInfo::AggInfo_func*)sqlite3ArrayAllocate(+
−
       db, +
−
       pInfo->aFunc,+
−
       sizeof(pInfo->aFunc[0]),+
−
       3,+
−
       &pInfo->nFunc,+
−
       &pInfo->nFuncAlloc,+
−
       &i+
−
  );+
−
  return i;+
−
}    +
−
+
−
/*+
−
** This is an xFunc for walkExprTree() used to implement +
−
** sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates+
−
** for additional information.+
−
**+
−
** This routine analyzes the aggregate function at pExpr.+
−
*/+
−
static int analyzeAggregate(void *pArg, Expr *pExpr){+
−
  int i;+
−
  NameContext *pNC = (NameContext *)pArg;+
−
  Parse *pParse = pNC->pParse;+
−
  SrcList *pSrcList = pNC->pSrcList;+
−
  AggInfo *pAggInfo = pNC->pAggInfo;+
−
+
−
  switch( pExpr->op ){+
−
    case TK_AGG_COLUMN:+
−
    case TK_COLUMN: {+
−
      /* Check to see if the column is in one of the tables in the FROM+
−
      ** clause of the aggregate query */+
−
      if( pSrcList ){+
−
		  SrcList::SrcList_item *pItem = pSrcList->a;+
−
        for(i=0; i<pSrcList->nSrc; i++, pItem++){+
−
			AggInfo::AggInfo_col *pCol;+
−
          if( pExpr->iTable==pItem->iCursor ){+
−
            /* If we reach this point, it means that pExpr refers to a table+
−
            ** that is in the FROM clause of the aggregate query.  +
−
            **+
−
            ** Make an entry for the column in pAggInfo->aCol[] if there+
−
            ** is not an entry there already.+
−
            */+
−
			  int k=0;+
−
            pCol = pAggInfo->aCol;+
−
            for(k=0; k<pAggInfo->nColumn; k++, pCol++){+
−
              if( pCol->iTable==pExpr->iTable &&+
−
                  pCol->iColumn==pExpr->iColumn ){+
−
                break;+
−
              }+
−
            }+
−
            if( (k>=pAggInfo->nColumn)+
−
             && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 +
−
            ){+
−
              pCol = &pAggInfo->aCol[k];+
−
              pCol->pTab = pExpr->pTab;+
−
              pCol->iTable = pExpr->iTable;+
−
              pCol->iColumn = pExpr->iColumn;+
−
              pCol->iMem = pParse->nMem++;+
−
              pCol->iSorterColumn = -1;+
−
              pCol->pExpr = pExpr;+
−
              if( pAggInfo->pGroupBy ){+
−
                int j, n;+
−
                ExprList *pGB = pAggInfo->pGroupBy;+
−
				ExprList::ExprList_item *pTerm = pGB->a;+
−
                n = pGB->nExpr;+
−
                for(j=0; j<n; j++, pTerm++){+
−
                  Expr *pE = pTerm->pExpr;+
−
                  if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable &&+
−
                      pE->iColumn==pExpr->iColumn ){+
−
                    pCol->iSorterColumn = j;+
−
                    break;+
−
                  }+
−
                }+
−
              }+
−
              if( pCol->iSorterColumn<0 ){+
−
                pCol->iSorterColumn = pAggInfo->nSortingColumn++;+
−
              }+
−
            }+
−
            /* There is now an entry for pExpr in pAggInfo->aCol[] (either+
−
            ** because it was there before or because we just created it).+
−
            ** Convert the pExpr to be a TK_AGG_COLUMN referring to that+
−
            ** pAggInfo->aCol[] entry.+
−
            */+
−
            pExpr->pAggInfo = pAggInfo;+
−
            pExpr->op = TK_AGG_COLUMN;+
−
            pExpr->iAgg = k;+
−
            break;+
−
          } /* endif pExpr->iTable==pItem->iCursor */+
−
        } /* end loop over pSrcList */+
−
      }+
−
      return 1;+
−
    }+
−
    case TK_AGG_FUNCTION: {+
−
      /* The pNC->nDepth==0 test causes aggregate functions in subqueries+
−
      ** to be ignored */+
−
      if( pNC->nDepth==0 ){+
−
        /* Check to see if pExpr is a duplicate of another aggregate +
−
        ** function that is already in the pAggInfo structure+
−
        */+
−
		  AggInfo::AggInfo_func *pItem = pAggInfo->aFunc;+
−
        for(i=0; i<pAggInfo->nFunc; i++, pItem++){+
−
          if( sqlite3ExprCompare(pItem->pExpr, pExpr) ){+
−
            break;+
−
          }+
−
        }+
−
        if( i>=pAggInfo->nFunc ){+
−
          /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]+
−
          */+
−
          u8 enc = ENC(pParse->db);+
−
          i = addAggInfoFunc(pParse->db, pAggInfo);+
−
          if( i>=0 ){+
−
            pItem = &pAggInfo->aFunc[i];+
−
            pItem->pExpr = pExpr;+
−
            pItem->iMem = pParse->nMem++;+
−
            pItem->pFunc = sqlite3FindFunction(pParse->db,+
−
                   (char*)pExpr->token.z, pExpr->token.n,+
−
                   pExpr->pList ? pExpr->pList->nExpr : 0, enc, 0);+
−
            if( pExpr->flags & EP_Distinct ){+
−
              pItem->iDistinct = pParse->nTab++;+
−
            }else{+
−
              pItem->iDistinct = -1;+
−
            }+
−
          }+
−
        }+
−
        /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry+
−
        */+
−
        pExpr->iAgg = i;+
−
        pExpr->pAggInfo = pAggInfo;+
−
        return 1;+
−
      }+
−
    }+
−
  }+
−
+
−
  /* Recursively walk subqueries looking for TK_COLUMN nodes that need+
−
  ** to be changed to TK_AGG_COLUMN.  But increment nDepth so that+
−
  ** TK_AGG_FUNCTION nodes in subqueries will be unchanged.+
−
  */+
−
  if( pExpr->pSelect ){+
−
    pNC->nDepth++;+
−
    walkSelectExpr(pExpr->pSelect, analyzeAggregate, pNC);+
−
    pNC->nDepth--;+
−
  }+
−
  return 0;+
−
}+
−
+
−
/*+
−
** Analyze the given expression looking for aggregate functions and+
−
** for variables that need to be added to the pParse->aAgg[] array.+
−
** Make additional entries to the pParse->aAgg[] array as necessary.+
−
**+
−
** This routine should only be called after the expression has been+
−
** analyzed by sqlite3ExprResolveNames().+
−
**+
−
** If errors are seen, leave an error message in zErrMsg and return+
−
** the number of errors.+
−
*/+
−
int sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){+
−
  int nErr = pNC->pParse->nErr;+
−
  walkExprTree(pExpr, analyzeAggregate, pNC);+
−
  return pNC->pParse->nErr - nErr;+
−
}+
−
+
−
/*+
−
** Call sqlite3ExprAnalyzeAggregates() for every expression in an+
−
** expression list.  Return the number of errors.+
−
**+
−
** If an error is found, the analysis is cut short.+
−
*/+
−
int sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){+
−
	ExprList::ExprList_item *pItem;+
−
  int i;+
−
  int nErr = 0;+
−
  if( pList ){+
−
    for(pItem=pList->a, i=0; nErr==0 && i<pList->nExpr; i++, pItem++){+
−
      nErr += sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr);+
−
    }+
−
  }+
−
  return nErr;+
−
}+
−