交易失敗，因為快照集隔離交易不允許使用此 DDL 陳述式。由於中繼資料並未建立版本，如果在快照集隔離下變更中繼資料，將會造成不一致的問題。

Transaction failed because this DDL statement is not allowed inside a snapshot isolation transaction. Since metadata is not versioned, a metadata change can lead to inconsistency if mixed within snapshot isolation.