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Comment:Increase the resolution of the second parameter to the likelihood() SQL function (the probability value) so that it can handle probabilities as small as 0.00000001. Formerly, it ran out of precision at 0.001.
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SHA1: 0f08924fe0c52a85a103f67bee9809e0f8f884b0
User & Date: drh 2014-10-25 13:42:16.126
Context
2014-10-27
11:25
Add test file e_wal.test. (check-in: fc6920b548 user: dan tags: trunk)
07:01
Merge trunk with this branch. (check-in: a13df3013b user: dan tags: defrag-opt)
2014-10-25
13:42
Increase the resolution of the second parameter to the likelihood() SQL function (the probability value) so that it can handle probabilities as small as 0.00000001. Formerly, it ran out of precision at 0.001. (check-in: 0f08924fe0 user: drh tags: trunk)
12:28
Do not use virtual (and hence redundant) WHERE-clause terms to restrict the content of a automatic partial index. Show when an automatic partial index is used in the EXPLAIN QUERY PLAN output. (check-in: b9ad601eab user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/resolve.c.
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*/
static int exprProbability(Expr *p){
  double r = -1.0;
  if( p->op!=TK_FLOAT ) return -1;
  sqlite3AtoF(p->u.zToken, &r, sqlite3Strlen30(p->u.zToken), SQLITE_UTF8);
  assert( r>=0.0 );
  if( r>1.0 ) return -1;
  return (int)(r*1000.0);
}

/*
** This routine is callback for sqlite3WalkExpr().
**
** Resolve symbolic names into TK_COLUMN operators for the current
** node in the expression tree.  Return 0 to continue the search down








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*/
static int exprProbability(Expr *p){
  double r = -1.0;
  if( p->op!=TK_FLOAT ) return -1;
  sqlite3AtoF(p->u.zToken, &r, sqlite3Strlen30(p->u.zToken), SQLITE_UTF8);
  assert( r>=0.0 );
  if( r>1.0 ) return -1;
  return (int)(r*134217728.0);
}

/*
** This routine is callback for sqlite3WalkExpr().
**
** Resolve symbolic names into TK_COLUMN operators for the current
** node in the expression tree.  Return 0 to continue the search down
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            ** EVIDENCE-OF: R-01283-11636 The unlikely(X) function is short-hand for
            ** likelihood(X,0.0625).
            ** EVIDENCE-OF: R-36850-34127 The likely(X) function is short-hand for
            ** likelihood(X,0.9375).
            ** EVIDENCE-OF: R-53436-40973 The likely(X) function is equivalent to
            ** likelihood(X,0.9375). */
            /* TUNING: unlikely() probability is 0.0625.  likely() is 0.9375 */
            pExpr->iTable = pDef->zName[0]=='u' ? 62 : 938;
          }             
        }
#ifndef SQLITE_OMIT_AUTHORIZATION
        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",








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            ** EVIDENCE-OF: R-01283-11636 The unlikely(X) function is short-hand for
            ** likelihood(X,0.0625).
            ** EVIDENCE-OF: R-36850-34127 The likely(X) function is short-hand for
            ** likelihood(X,0.9375).
            ** EVIDENCE-OF: R-53436-40973 The likely(X) function is equivalent to
            ** likelihood(X,0.9375). */
            /* TUNING: unlikely() probability is 0.0625.  likely() is 0.9375 */
            pExpr->iTable = pDef->zName[0]=='u' ? 8388608 : 125829120;
          }             
        }
#ifndef SQLITE_OMIT_AUTHORIZATION
        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",
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Changes to src/sqliteInt.h.
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#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old
                         ** EP_Unlikely:  1000 times likelihood */
  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1). */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
  u8 op2;                /* TK_REGISTER: original value of Expr.op
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */








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#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old
                         ** EP_Unlikely:  134217728 times likelihood */
  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1). */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
  u8 op2;                /* TK_REGISTER: original value of Expr.op
                         ** TK_COLUMN: the value of p5 for OP_Column
                         ** TK_AGG_FUNCTION: nesting depth */
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Changes to src/where.c.
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    if( pOld!=pWC->aStatic ){
      sqlite3DbFree(db, pOld);
    }
    pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
  }
  pTerm = &pWC->a[idx = pWC->nTerm++];
  if( p && ExprHasProperty(p, EP_Unlikely) ){
    pTerm->truthProb = sqlite3LogEst(p->iTable) - 99;
  }else{
    pTerm->truthProb = 1;
  }
  pTerm->pExpr = sqlite3ExprSkipCollate(p);
  pTerm->wtFlags = wtFlags;
  pTerm->pWC = pWC;
  pTerm->iParent = -1;








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    if( pOld!=pWC->aStatic ){
      sqlite3DbFree(db, pOld);
    }
    pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
  }
  pTerm = &pWC->a[idx = pWC->nTerm++];
  if( p && ExprHasProperty(p, EP_Unlikely) ){
    pTerm->truthProb = sqlite3LogEst(p->iTable) - 270;
  }else{
    pTerm->truthProb = 1;
  }
  pTerm->pExpr = sqlite3ExprSkipCollate(p);
  pTerm->wtFlags = wtFlags;
  pTerm->pWC = pWC;
  pTerm->iParent = -1;
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