用一句話概括冷備,就是把數據庫服務,比如MySQL,Oracle停下來,然后使用拷貝、打包或者壓縮命令對數據目錄進行備份。如果數據出現異常,則可以通過備份數據恢復。冷備一般需要定制計劃,比如什么時候做備份,每次對哪些數據進行備份等等。但是由于這樣的備份占用過多的空間,對大數據量的環境下不一定適合,故生產環境很少使用。
冷備示意圖
冷備實驗
第一步,創建測試數據庫,插入測試數據
| mysql> use larrydb;Database changedmysql> show tables;+-------------------+| Tables_in_larrydb |+-------------------+| access |+-------------------+1 row in set (0.00 sec)mysql> drop table access;Query OK, 0 rows affected (0.00 sec)mysql> clearmysql> show tables;Empty set (0.00 sec)mysql> mysql> create table class( -> cid int, -> cname varchar(30));Query OK, 0 rows affected (0.01 sec)mysql> show create table class /G;*************************** 1. row *************************** Table: classCreate Table: CREATE TABLE `class` ( `cid` int(11) DEFAULT NULL, `cname` varchar(30) DEFAULT NULL) ENGINE=InnoDB DEFAULT CHARSET=latin11 row in set (0.00 sec)ERROR: No query specifiedmysql> create table stu( -> sid int, -> sname varchar(30), -> cid int) engine=myisam;Query OK, 0 rows affected (0.00 sec)mysql> show create table stu /G;*************************** 1. row *************************** Table: stuCreate Table: CREATE TABLE `stu` ( `sid` int(11) DEFAULT NULL, `sname` varchar(30) DEFAULT NULL, `cid` int(11) DEFAULT NULL) ENGINE=MyISAM DEFAULT CHARSET=utf81 row in set (0.00 sec)ERROR: No query specifiedmysql> insert into class values(1,'linux'),(2,'oracle');Query OK, 2 rows affected (0.00 sec)Records: 2 Duplicates: 0 Warnings: 0mysql> desc class;+-------+-------------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra |+-------+-------------+------+-----+---------+-------+| cid | int(11) | YES | | NULL | || cname | varchar(30) | YES | | NULL | |+-------+-------------+------+-----+---------+-------+2 rows in set (0.00 sec)mysql> desc stu;+-------+-------------+------+-----+---------+-------+| Field | Type | Null | Key | Default | Extra |+-------+-------------+------+-----+---------+-------+| sid | int(11) | YES | | NULL | || sname | varchar(30) | YES | | NULL | || cid | int(11) | YES | | NULL | |+-------+-------------+------+-----+---------+-------+3 rows in set (0.00 sec)mysql> insert into stu values(1,'larry01',1),(2,'larry02',2);Query OK, 2 rows affected (0.00 sec)Records: 2 Duplicates: 0 Warnings: 0mysql> select * from stu;+------+---------+------+| sid | sname | cid |+------+---------+------+| 1 | larry01 | 1 || 2 | larry02 | 2 |+------+---------+------+ |