Redis提供了丰富的命令对数据库和各种数据类型进行操作。 (1)keys 返回满足给定pattern的所有键值。例如返回所有的key用:keys
Redis提供了丰富的命令对数据库和各种数据类型进行操作。
(1)keys
返回满足给定pattern的所有键值。例如返回所有的key用:keys *
(2)exists
确认一个key是否存在。
(3)del
删除一个键。例如:del name
(4)expire
设置一个键的过期时间。例如:expire age 10,10s后过期。
(5)ttl
查看还有多长时间过期。比如:ttl age,过期后返回-1。
(6)move
将当前数据库中的key转移到其它数据库中。当然在这之前,我们要先选择数据库,用select语句。
比如select 0表示选择0数据库,在Redis中,一共有16个数据库,分别是0~15,一般情况下,进入数据
库默认编号是0,如果我们要进入指定数据库,可以用select语句,select 1表示进入编号为1的数据库。
现在,我们要把0号数据库中的age移动到1号数据库,,那么直接:move age 1
(7)persist
移除给定key的过期时间。例如:persist age
(8)randomkey
随机返回数据库中的一个键。例如:randomkey
(9)rename
重命名key。例如:rename age age1,表示把age重命名为age1
(10)type
返回键值的类型。比如:type age
(11)echo
打印一些内容。例如:echo name,就输出"name"。
(12)quit
退出连接。
(13)dbsize
返回当前数据库中所有key的数目。
(14)info
获取服务器的信息和统计。
(15)config get
实时传储收到的请求。例如:config get dir
(16)flushdb
删除当前数据库中的所有key。
(17)flushall
清空所有数据库中的所有key。
Redis数据库的高级应用
(1)为Redis数据库设置密码
只需要在redis的配置文件中设置requirepass后面加上自己指定的密码就行了。启动的时候再指定配置
文件。进入客户端后,我们发现能进入但是各种操作均被拒绝,所以我们还要进行授权,利用语句auth跟上
密码即可。也可以登录客户端的时候输入密码,例如:redis-cli -a 88888888。
(2)redis主从复制
redis主从复制的特点:
1.一个master可以拥有多个slave
2.多个slave可以连接同一个master外,还可以连接到其它slave
3.主从复制不会阻塞master,在同步数据时,master可以继续处理client的请求
4.提高系统的伸缩性
redis主从复制过程:
1.slave与master建立连接,发送sync同步命令
2.master会启动一个后台进程,将数据库快照保存到文件中,同时master主进程会开始收集新的写命令
并缓存。
3.后台完成保存后,就将此文件发送给slave
4.slave将此文件保存到硬盘上
配置主从服务器:
配置slave服务器很简单,只需要在slave的配置文件中加入以下配置:
slaveof 222.27.174.98 6379 //指定master的主机的IP和端口号
masterauth 888888 //主机数据库的密码
我们可以通过info命令来查看本机的redis是主服务器还是从服务器。
Ubuntu 14.04下Redis安装及简单测试
Redis集群明细文档
Ubuntu 12.10下安装Redis(图文详解)+ Jedis连接Redis
Redis系列-安装部署维护篇
CentOS 6.3安装Redis
Redis安装部署学习笔记
Redis配置文件redis.conf 详解
Redis 的详细介绍:请点这里
Redis 的下载地址:请点这里
本文永久更新链接地址:

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