SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function mapFilter (children 1)
     ExpressionList (children 2)
      Function lambda (children 1)
       ExpressionList (children 2)
        Function tuple (children 1)
         ExpressionList (children 2)
          Identifier x
          Identifier y
        Function toInt32 (children 1)
         ExpressionList (children 1)
          Identifier x
      Function map (children 1)
       ExpressionList (children 4)
        Literal UInt64_1
        Literal UInt64_0
        Literal UInt64_2
        Literal UInt64_0