SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 4)
    Literal Float64_-inf (alias x)
    Function not (children 1)
     ExpressionList (children 1)
      Identifier x
    Function not (children 1)
     ExpressionList (children 1)
      Function not (children 1)
       ExpressionList (children 1)
        Identifier x
    Function isNull (children 1)
     ExpressionList (children 1)
      Function not (children 1)
       ExpressionList (children 1)
        Identifier x
   Set