MySQL5.7 OCP每日一题--Question: 10

Question: 10

You have just executed a manual backup by using this command: 
mysqlbackup -u root -p --socket=/tmp/my.sock --backup-dir=/my/backup/ backup The operation completed without error. 
What is the state of this backup and operation required before it is ready to be restored? 
A. Backup State = Compressed Backup; Operation = copy-back 
**B. Backup State = Raw Backup; Operation = apply-log 
**C. Backup State = Prepared Backup; Operation = validate 
D. Backup State = Prepared Backup; Operation = apply-log 
E. Backup State = Raw Backup; Operation = backup-dir-to-image 
复制

答案：B
解析：mysqlbackup支持压缩备份，需要使用参数–compress指定，默认关闭。以上命令执行的是全量备份，完成后是原始备份状态，要执行还原需要先执行apply-log操作；apply-log完成后，备份状态变为prepard backup，此时可以执行validate操作检查备份是否完整可用。检查完成后进行copy-back操作、修改数据目录权限、启动mysqld进程等操作后恢复完成。