public static IAcceptsJoin LeftJoin(this IAcceptsJoin @this, string tableName, string constraint)
 {
     @this.Accept(new JoinClause(new TableOrSubQuery(tableName), constraint)
     {
         JoinType = "LEFT"
     });
     return(@this);
 }
 public static IAcceptsJoin LeftJoin(this IAcceptsJoin @this, string tableName, string constraint, string alias)
 {
     @this.Accept(new JoinClause(tableName, constraint, alias)
     {
         JoinType = "LEFT"
     });
     return(@this);
 }
 public static IAcceptsJoin LeftJoin(this IAcceptsJoin @this, TableOrSubQuery source, string constraint)
 {
     @this.Accept(new JoinClause(source, constraint)
     {
         JoinType = "LEFT"
     });
     return(@this);
 }