SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function length (children 1)
     ExpressionList (children 1)
      Function HMAC (children 1)
       ExpressionList (children 3)
        Literal \'sha256\'
        Literal \'test\'
        Literal \'key\'
