SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function less (children 1)
     ExpressionList (children 2)
      Function abs (children 1)
       ExpressionList (children 1)
        Function minus (children 1)
         ExpressionList (children 2)
          Function tan (children 1)
           ExpressionList (children 1)
            Function divide (children 1)
             ExpressionList (children 2)
              Function pi (children 1)
               ExpressionList
              Literal UInt64_4
          Literal UInt64_1
      Literal Float64_1e-9