Un7.27: common commands of redis database.

Today, I'd like to share with you some things I've been exposed to redis command .

One 、 brief introduction .

redis Is an open source in-memory data structure storage system , It can be used as a database / Caching and message middleware . In the form of key value pairs （key-value）, Per second /10 ten thousand ++.

Two 、 Database type .

We often see two kinds of databases , A is MySQL,Oracle,DB2,SQLServer Mainly relational database , There is another kind. , That is to say Redis,mongo db,Memcached Mainly non relational database .

3、 ... and 、 effect .

redis As a typical non relational database , Not only has the function of caching , And it can also queue tasks 、 Message queue , And distributed locking , It provides great convenience for our programmers .

Four 、 data type .

redis In order to key-value Key value pairs exist in the form of ,key Is string ,value There are five common .
1、 character string ：String 

2、 Hash ：hash  Suitable for storing objects

3、 list ：list  Sequence list , Can have repeating elements

4、 aggregate ：set  unordered set , There can be no repeating elements

5、 Ordered set ：sorted set  Ordered set , There can be no repeating elements （ Ranking List ）

5、 ... and 、String String common commands .

1、 assignment ：set key（name） value（xiaoai）

2、 Get value , Post value override ：get key（name）

3、 Survival time ：setex key（ City ） seconds（10） value（taiyuan）

4、key Set value when it does not exist , Existence is invariable ：setnx key value

6、 ... and 、hash Hash common commands .

1、 take key In the field field The value of the set value, command ：Hset key（001） field（name） value（xiaoai）

2、 Get the specified field , command ：Hset key field

3、 Delete the specified field , command ：Hdel key field

4、 Get all fields , command ：Hkeys key

5、 Get all values , command ：Hvals key

6、 Get specified key All fields and values of , command ：Hgetall key

7、 ... and 、list Common commands .

1、 Insert one or more values into the list header , command ：Lpush key value1 [value2,value3......]

2、 Get the elements in the specified range of the list , command ：LRange key start stop

3、 Remove and get the last element of the list , command ：Rpop key

4、 Get list length , command ：Llen key

5、 Remove and get the last element of the list , Or find pop-up elements , command ：BRpop key1 [key2] timeout

8、 ... and 、set Set common commands .

1、 Add multiple members . command ：sadd key 1 2

2、 Back to the assembly , command ：smembers key

3、 How many? , command ：scard key

4、 intersection 、 share . command ：sinter key1,key2

5、 Combine , command ：sunion key1,key2

6、 Difference set , The following element does not exist , command ：sdiff key1,key2

7、 remove , command ：SRem key key1,key2

Nine 、sorted set command .

1、 Add one or more （ Sort from small to large ）, command ：zadd key score1 member1 [score2 member2]

2、 Gets the specified range element , command ：zrange key star stop[with scores]

3、 Revise the score , command ：zincrby key increment（ How much to add ） member（ member ）

4、 Remove one or more elements , command ：zrem key member

Ten 、 General Command .

1、 Find all that match key, command ：keys pattern

2、 Check the given key Whether the value exists , command ：exists key

3、 return key The type of value stored , command ：type key

4、 Return to a given key The remaining lifetime of ( second ), command ：ttl key

5、 This command is used in key Delete... When it exists key（ Not shown here ）, command ：del key

That's what I sum up about redis Common commands , Of course , You can also collect more commands to improve your knowledge system , For daily use , These are basically enough , Good luck .