SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function and (alias r) (children 1)
     ExpressionList (children 2)
      Function notEquals (children 1)
       ExpressionList (children 2)
        Function acos (children 1)
         ExpressionList (children 1)
          Identifier a
        Function atan (children 1)
         ExpressionList (children 1)
          Identifier b
      Function not (children 1)
       ExpressionList (children 1)
        Function notEquals (children 1)
         ExpressionList (children 2)
          Function acos (children 1)
           ExpressionList (children 1)
            Identifier a
          Function atan (children 1)
           ExpressionList (children 1)
            Identifier b
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 2)
           Literal UInt64_2 (alias a)
           Literal UInt64_2 (alias b)
