SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function lessOrEquals (children 1)
     ExpressionList (children 2)
      Function minus (children 1)
       ExpressionList (children 2)
        Function dateDiff (children 1)
         ExpressionList (children 3)
          Literal \'second\'
          Function toDate32 (children 1)
           ExpressionList (children 1)
            Literal \'2015-08-18\'
          Function toDate (children 1)
           ExpressionList (children 1)
            Literal \'2015-08-19\'
        Function timeDiff (children 1)
         ExpressionList (children 2)
          Function toDate32 (children 1)
           ExpressionList (children 1)
            Literal \'2015-08-18\'
          Function toDate (children 1)
           ExpressionList (children 1)
            Literal \'2015-08-19\'
      Literal UInt64_2