SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Identifier v1
    Identifier v2
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier primary_key_test
   ExpressionList (children 2)
    OrderByElement (children 1)
     Identifier v1
    OrderByElement (children 1)
     Identifier v2
