最后一个条件可用于尝试并估计数据更改(即，如果数据库中的数据自最后一次备份以来没有发生变化，则不必进行新的备份)。

This last criterion can be used to try and estimate the data change (that is, if data in the database has not changed since last backup, there is no need to take a new backup).

youdao

我的好朋友和商业伙伴开玩笑说他成为一个数据库管理员是因为SQL已经35年没有变化了，这大部分是真的。

My good friend and business partner jokes that he became a DBA because SQL hasn't changed in 35 years. This is, largely, true.

youdao

只要数据库发生了变化，备份可以是离线(没有用户连接到数据库)或在线进行的。

Backups can be taken offline (when no users are connected to the database) or online, as the database is being changed.

youdao