基于时间点的恢复依赖的是 binlog 日志,需要从 binlog 中找过从备份点到恢复点的所有日志,然后应用。我们测试一下。
新建测试表:
chengqm-3306>>show create table mytest.mytest \G;
*************************** 1. row ***************************
Table: mytest
Create Table: CREATE TABLE `mytest` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`ctime` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
每秒插入一条数据:
[mysql@mysql-test ~]$ while true; do mysql -S /tmp/mysql.sock -e 'insert into mytest.mytest(ctime)values(now())';date;sleep 1;done
备份:
[mysql@mysql-test ~]$ mysqldump --opt --single-transaction --master-data=2 --default-character-set=utf8 -S /tmp/mysql.sock -A > backup.sql
找出备份时的日志位置:
[mysql@mysql-test ~]$ head -n 25 backup.sql | grep 'CHANGE MASTER TO MASTER_LOG_FILE'
-- CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000032', MASTER_LOG_POS=39654;
假设要恢复到 2019-08-09 11:01:54 这个时间点,我们从 binlog 中查找从 39654 到 019-08-09 11:01:54 的日志。
[mysql@mysql-test ~]$ mysqlbinlog --start-position=39654 --stop-datetime='2019-08-09 11:01:54' /data/mysql_log/mysql_test/mysql-bin.000032 > backup_inc.sql
[mysql@mysql-test-83 ~]$ tail -n 20 backup_inc.sql
......
......
当前数据条目数:
-- 2019-08-09 11:01:54之前的数据条数
chengqm-3306>>select count(*) from mytest.mytest where ctime < '2019-08-09 11:01:54';
+----------+
| count(*) |
+----------+
| 161 |
+----------+
1 row in set (0.00 sec)
-- 所有数据条数
chengqm-3306>>select count(*) from mytest.mytest;
+----------+
| count(*) |
+----------+
| 180 |
+----------+
1 row in set (0.00 sec)
然后执行恢复:
[mysql@mysql-test ~]$ mysql -S /tmp/mysql.sock < backup.sql
[mysql@mysql-test ~]$ mysql -S /tmp/mysql.sock < backup_inc.sql
检查数据:
chengqm-3306>>select count(*) from mytest.mytest;
+----------+
| count(*) |
+----------+
| 161 |
+----------+
1 row in set (0.00 sec)
chengqm-3306>>select * from mytest.mytest order by id desc limit 5;
+-----+---------------------+
| id | ctime |
+-----+---------------------+
| 161 | 2019-08-09 11:01:53 |
| 160 | 2019-08-09 11:01:52 |
| 159 | 2019-08-09 11:01:51 |
| 158 | 2019-08-09 11:01:50 |
| 157 | 2019-08-09 11:01:49 |
+-----+---------------------+
5 rows in set (0.00 sec)
已经恢复到 2019-08-09 11:01:54 这个时间点。