SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test1
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier test2
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier test1.col1
        Identifier test2.col1
   Function isNull (children 1)
    ExpressionList (children 1)
     Identifier test2.col1
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier test2.col1