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SQLite training in Houston TX on 2019-11-05 (details)
Part of the 2019 Tcl Conference

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Overview
Comment:Use NOT NULL partial indexes when the query is constrained by a single LIKE or GLOB.
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SHA1: 9b3a3b41b59a7ce7d3dd82c7402d6fdc6a5ca43c
User & Date: drh 2016-11-02 02:17:52
Context
2016-11-02
13:18
Fix a requirement mark. No changes to code. check-in: d18f61b7 user: drh tags: trunk
02:17
Use NOT NULL partial indexes when the query is constrained by a single LIKE or GLOB. check-in: 9b3a3b41 user: drh tags: trunk
2016-10-31
16:49
Add the SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE sqlite3_dbconfig() option - for disabling SQLite's default checkpoint-on-close behaviour. check-in: 6d142025 user: dan tags: trunk
Changes
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Changes to src/expr.c.

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  }
  if( pE2->op==TK_OR
   && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
             || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
  ){
    return 1;
  }
  if( pE2->op==TK_NOTNULL
   && sqlite3ExprCompare(pE1->pLeft, pE2->pLeft, iTab)==0
   && (pE1->op!=TK_ISNULL && pE1->op!=TK_IS)
  ){
    return 1;
  }
  return 0;
}

/*
** An instance of the following structure is used by the tree walker
** to determine if an expression can be evaluated by reference to the







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  }
  if( pE2->op==TK_OR
   && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
             || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
  ){
    return 1;
  }
  if( pE2->op==TK_NOTNULL && pE1->op!=TK_ISNULL && pE1->op!=TK_IS ){
    Expr *pX = sqlite3ExprSkipCollate(pE1->pLeft);
    testcase( pX!=pE1->pLeft );
    if( sqlite3ExprCompare(pX, pE2->pLeft, iTab)==0 ) return 1;

  }
  return 0;
}

/*
** An instance of the following structure is used by the tree walker
** to determine if an expression can be evaluated by reference to the