SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 1)
    WithElement (children 1)
     Subquery (children 1)
      SelectWithUnionQuery (children 1)
       ExpressionList (children 1)
        SelectQuery (children 3)
         ExpressionList (children 2)
          Identifier n
          Literal NULL (alias b)
         TablesInSelectQuery (children 1)
          TablesInSelectQueryElement (children 1)
           TableExpression (children 1)
            TableIdentifier with_test
         Function isNull (children 1)
          ExpressionList (children 1)
           Identifier b
   ExpressionList (children 1)
    Function max (children 1)
     ExpressionList (children 1)
      Identifier n
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test1
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier n
     Literal UInt64_42
