redis--Introduction && Installation (1)

Non-relational database characteristics:

1. The data model is relatively simple, the key corresponds to a value, and the data is stored in memory
2. Need a more flexible it system
3. Relatively high database performance requirements
4. No need for high data consistency
5. For a given key, it is easier to map a complex environment

Redis features

It is stored in the form of key_value, which is different from traditional relational databases, and does not necessarily follow some basic requirements of traditional databases (non-relational, distributed, open source and horizontally scalable)

advantage:

1. High concurrent reading and writing of data, one is memory level read and write and the other is hard disk level read and write
2. Efficient storage and access to massive data
3. Scalability and high availability of data

Disadvantages:

1. redis (ACID processing is very simple)
2. Can't do too complicated relational database

The redis key can contain String strings, hashes, list linked lists, set collections, zset ordered collections, these data collections all support push/pop, add/remove, intersection and union, and richer operations. Redis supports various Sorting in different ways, in order to ensure efficiency, the data is cached in the memory, or the updated data can be periodically written to the disk, and the modification operation can be written and appended to the file.

redis installation:

    
    yum install -y wget gcc
    systemctl stop firewalld.service
    systemctl disable firewalld.service
    cd /usr/local
    下载redis
    wget http://download.redis.io/releases/redis-5.0.3.tar.gz
    解压
    tar zxvf redis-5.0.3.tar.gz
    cd redis-5.0.3.tar.gz
    编译
    make
    cd src
    安装
    make install
    建立两个文件夹用来存放redis的命令和配置文件
    mkdir -p /usr/local/redis/etc 
    mkdir -p /usr/local/redis/bin
    把redis.conf 移动到etc下
    cd /usr/local/redis/etc
    cp /usr/local/redis-5.0.3/redis.conf .
    把redis/src里的 mkreleasehdr.sh  redis-benchmark redis-check-aof redis-cli redis-server复制到bin 
    启动redis
    redis-server /usr/local/redis/etc/redis.conf 
    ctrl + c 退出redis

Background start

Modify redis.conf and find the following value no change to yes

daemonize yes
restart 

redis client operation redis

keys * View data

Set value to get value

Stop redis server

/usr/local/redis/bin/redis-cli shutdown

The file where redis stores data is .rdb