catalogue
Add and delete the value of key
string
Stored data: single data
Data format: one storage space holds one data
basic operation
Add and modify data
set key value #Add single data mset key1 value1 key2 value2 key3 value3... #Add multiple data through key append key value #If there is data, append. If there is no data, create a new operation. After appending, return the length of the string
get data
Get value through key, return value if there is data, and nil if there is no data
get key #Get value through key, return value if there is data, and nil if there is no data mget key1 key2 key3 #Get multiple data strlen key #Get the length of string through key
Delete data
If (integer)1 is returned after deletion, the deletion is successful; If (integer)0 is returned, the deletion fails
del key
Add and delete the value of key
incr key #Add 1 incrby key increment #Increase the specified value of the data #Examples incrby id 10 #Add 10 incrbyfloat key increment #Append decimals to data #Examples incrbyfloat id 0.1 #Add 0.1 decr key #Minus 1
Set the life time of the key
When the set time is up, go to get and a nil will be returned
setex key seconds value #Seconds write time is in seconds psetex key milliseconds value #Millicons write time in milliseconds
hash
A key corresponds to many data, including field and value. A field corresponds to a value, that is, a key corresponds to the data of multiple key value pairs
The main purpose is to store data
basic operation
Add and modify data
hset key field value #Compared with string, you need to write more field s and insert a single data hmset key field value field1 value1 field2 value2 #Insert multiple data
get data
hget key field #Get single data through key and field hmget key field1 field2 field3.. #Get multiple data through key hgetall key field #Get all data through key and field hkeys key #Query all key s hvals key #Query all values
Delete data
hdel key field field1 field2... #Return (integer)1 means success and 0 means failure
Check for data
hlen key #Get length hexists key field #Check whether it is empty. If 0 is returned, it means there is no data in 1
listÂ
Multiple data can be saved. The bottom layer adopts the structure of two-way linked list to distinguish the order of data entry, which can reflect the order of entry
basic operation
Add and modify data
lpush key value value1 value2... #Add from the left rpush key value value1 value2... #Add from the right
Get data
#Get data through the index range. If you add data output through lpush, it is in reverse order. If you add data output through rpush, it is in order lrange key start stop #Example 1: lrange student 0 10 means to obtain data from index 0 to index 10 #Example 2: lrange student 0 -1, where - 1 represents the last one, you can view all #Get data by index lindex key start stop #Example: lindex student 10 obtains the data of index 10 #View length len key #Get and remove the data, take out the data, print it, and remove it from the list lpop key #Get and remove from left rpop key #Get and remove from the right #Obtain and remove the data within the specified time blpop key key1 timeout brpop key key1 timeout #Example: blpop student 15 adds data within 15 seconds, and the operation instruction acquires and removes the data. After 15 seconds, the data disappears
set
Compared with hash, if the key is cancelled, a field corresponds to a value, which provides a higher internal storage mechanism, makes it easier to query efficiently, and the value cannot be repeated
basic operation
Add data
sadd key member member1... #Return 1 for success and 0 for failure
get data
smembers key #Get all data through key scard key #Total amount of data obtained sismember key member #Judge whether there is a specified member, 1 means include, 0 means not include
Delete data
srem key member member1... #Delete data through key
sorted_set
The storage structure based on set provides a sort method, which is more conducive to the display of data
basic operation
Add data
zadd key score member score1 member1... #Example: zadd student 8 kobe
Get data
#Total data obtained zcard key #Get the total amount of data by conditions zcount key min max #The score is output in ascending order. If whitscore is added, member and score will be displayed. If it is not added, only member will be displayed zrange key start stop whitscores #Example: zrange student 0 -1, where 0 means to start from 0 and - 1 means to print all from the last one #The score is output in descending order. If whitscore is added, member and score will be displayed. If it is not added, only member will be displayed zrevrange key start stop whitscores #Example: zrevrange student 0 -1, where 0 means to start from 0 and - 1 means to print all from the last #Data acquisition according to the required conditions (ascending order) zrangebyscore key min max withscores #Example: zrangebyscore student 40 60 whitscores indicates students who have obtained 40-60 #Obtain the data according to the required conditions (in descending order) zrevrangebyscore key min max withscores #Example: zrevangebyscore student 40 60 whitscores indicates students who have obtained 40-60 #After the summation operation of the intersection of sets, the query will be displayed. Note: only the data of all sets will be summated zinterstore destination numkeys key key1 #Example: zinterstore destination (name of newly saved set) numkeys (number of sets to operate) key (key name of operation) key1
Delete data
#Delete data through key zrem key member member1... #Delete data by condition zremrangbyrank key start stop zremrangebyscore key min max
Sort data
#Sort in ascending order by index zrank key member #For example: zrank student kobe will output the ranking of kobe (the return form is index) #Descending by index zreverank key member