将分割镜像初始化为快照时，将执行崩溃恢复，回滚所有未提交的事务，并使数据库可以被所有读或写操作访问。

The initialization of the split mirror as snapshot performs a crash recovery, rolls back all uncommitted transactions, and makes the database available for any read or write operation.

youdao

例如，如果一个成员正在更新一行数据，那么另一个成员就不能以未提交读(uncommitted read)以外的任何隔离级别读取这一行。

For example, if one member is updating a row, it would not be proper for another member to read the row with any other isolation level than uncommitted read.

youdao

脏读：A 1检索a 2未提交的数据。

Dirty reads: A1 is retrieving uncommitted data of a2.

youdao

比如，读取只读的查找表不需要可重复读级别，未提交读级别就足够了。

For example, reading from a read - only look up table doesn t require repeatable read, and uncommitted read is sufficient.

youdao

比如，读取只读的查找表不需要可重复读级别，未提交读级别就足够了。

For example, reading from a read - only look up table doesn t require repeatable read, and uncommitted read is sufficient.

youdao