一、Mysql逻辑备份 1. 使用mysqldump命令生成INSERT语句备份 此方法类似于Oracle的expdp\exp工具 语法如下: mysqldump [argum
一、Mysql逻辑备份
1. 使用mysqldump命令生成INSERT语句备份
此方法类似于Oracle的expdp\exp工具
语法如下:
mysqldump [arguments] > file_name.sql
使用帮助:
[root@gc ~]# mysqldump
Usage: mysqldump [OPTIONS] database [tables]
OR mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR mysqldump [OPTIONS] --all-databases [OPTIONS]
For more options, use mysqldump --help
备份实例:
备份所有数据库
# mysqldump -uroot -proot --all-database > /tmp/dumpback/alldb.sql
备份某些数据库
# mysqldump -uroot -proot --database sqoop hive > /tmp/dumpback/sqoop_hive.sql
备份某数据库中的表
# mysqldump -uroot -proot sqoop tb1 > /tmp/dumpback/sqoop_tb1.sql
查看备份内容:
[root@gc dumpback]# more sqoop_tb1.sql
-- MySQL dump 10.13 Distrib 5.5.24, for Linux (x86_64)
--
-- Host: localhost Database: sqoop
-- ------------------------------------------------------
-- Server version 5.5.24
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
......
--
-- Table structure for table `tb1`
--
DROP TABLE IF EXISTS `tb1`;
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `tb1` (
`table_schema` varchar(64) CHARACTER SET utf8 NOT NULL DEFAULT '',
`table_name` varchar(64) CHARACTER SET utf8 NOT NULL DEFAULT '',
`table_type` varchar(64) CHARACTER SET utf8 NOT NULL DEFAULT ''
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;
--
-- Dumping data for table `tb1`
--
LOCK TABLES `tb1` WRITE;
/*!40000 ALTER TABLE `tb1` DISABLE KEYS */;
INSERT INTO `tb1` VALUES ('information_schema','CHARACTER_SETS','SYSTEM VIEW')
......
/*!40000 ALTER TABLE `tb1` ENABLE KEYS */;
UNLOCK TABLES;
/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;
.....
-- Dump completed on 2013-03-25 18:26:53
注意事项:
如何保证数据备份的一致性?
要想保证数据的一致性可以通过以下两种方法做到:
第一、同一时刻取出所有数据
对于事务支持的存储引擎,如Innodb 或者BDB 等,可以通过控制将整个备份过程在同一个事务中,使用“--single-transaction”选项。
例如:
# mysqldump --single-transaction test > test_backup.sql
第二、数据库中的数据处于静止状态
通过锁表参数
--lock-tables 每次锁定一个数据库的表,此参数是默认为true(见上面备份内容实例);
--lock-all-tables 一次锁定所有的表,适用于dump的表分别处于各个不同的数据库中的情况

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