If the user chooses to delete, the set of selected appointments is marked as invalid in the record store.

如果用户选择删除，所选择的这组约会在记录存储中被标记为无效。

youdao

All that DB2 does is to allow an UPDATE, DELETE, and INSERT to appear in the from clause of a select and allow the user to chose which transition table shall be selected from.

DB 2所做的就是允许UPDATE、DELETE和INSERT出现在选择语句的from子句中，并允许用户选择应该从哪个过渡表进行选择。

youdao