Today we will take a look at the installation and use of redis. Everything is summarized for easy use in the future.
The data stored in redis is in the form of KV, which can be persisted.
First, we need to install it first. What I choose here is to download the source code package online, and then compile it.
cd /opt
wget http://download.redis.io/releases/redis-4.0.8.tar.gz
After downloading, we need to unzip
tar -zxvf redis-4.0.8.tar.gz
After decompression, enter the folder and execute the make command to compile
cd redis-4.0.8
make
After compiling, we need to install and point to the installation directory, without spaces around the equal sign
cd bin
make install PREFIX=/usr/local/redis-4.0.8
After that, we copy redis.conf to our installation directory
cp redis.conf /usr/local/redis-4.0.8/redis.conf
The relevant configuration items in the configuration file are explained in my other blogs. You can refer to what you need to change.
For better operation, I only change one of the configurations, which is to change daemonize no to yes, and let it be in the background run
cd /usr/local/redis-4.0.8
vim redis.conf
After the modification, we can start
cd bin
./redis-server ../redis.conf
We can check whether there is redis in the process
ps -aux|grep redis
Redis runs in a single thread and can process about 100,000 requests per second. This needs to be combined with the host's hardware. We can run the command to check it. My machine is about 70,000.
./redis-benchmark
Well, now, we can connect to the redis client to try various commands.
Connect to the client. You can also say that the
default connection for something is 6379, so if our port has not been changed, we can directly execute the command to connect redis client
./redis-cli
If we modify the port to 6378, then the port needs to be added when connecting, including if there are multiple redis instances locally, then the port needs to be added when using the client to connect to redis
./redis-cli -p 6378
There is also a remote connection. At this time, you need to add ip. If the port is not the default 6379, you also need to add the port. If a password is set in the configuration file, then you need to add a password.
./redis-cli -h ip -p 端口 -a 密码
We can also connect first, and then enter the password to verify
auth password
OK, the client is connected, we can send a password ping, and will reply with a PONG to
get a value in the configuration file
config get key
Set a value in the configuration file
config set key value
The configuration file defaults to 16 databases, we can switch the database by command
select 切换的库下标
View the current number of library keys
DBSIZE
I want to see what specific keys are
keys *
If we want to match a key, we can use? As a placeholder, which only occupies one digit. For example, the matching key is k2
keys k?
Determine whether a key exists, return 1 if it exists, return 0 if it does not exist
EXISTS 查询的key
Remove a key-value pair from the current library and move it to another library
move 移除的key 移动到的库索引
Check how many seconds have expired, -1 means never expire, -2 means expired
ttl key
Set the expiration time for the given key, it will not exist after expiration
expire key 秒钟
Check what type of your key is
type key
Add value. There are five types of values: String, List, Set, Hash, and Zset sorted set.
String
String is the most basic type of Redis. You can understand it as exactly the same type as Memcached. A key corresponds to a value.
The String type is binary safe, meaning that the Redis String can contain any data, such as jpg images or serialized objects.
The String type is the most basic data type of Redis. The string value in a Redis can be up to 512M.
Settings
set key value
Delete key
del key
Append value
append key value
View length
STRLEN key
When the value is a number, you can directly add one
INCR key
When the value is a number, you can directly subtract one
DECR key
When the value is a number, it can be added directly
INCRBY k2 value
When the value is a number, it can be subtracted directly
DECRBY k2 value
Get the value between the start index and the end index, when the end index is -1, it is the end
GETRANGE key 开始下标 结束下标
Set value override
SETRANGE key 开始下标 替换的值
Set the value and set the expiration time
setex key 过期时间 value
If there is no setting value, it will not be overwritten if it exists
setnx key value
Set multiple values
mset key value key value key value ......
Get multiple values
mget key key key ......
Make multiple non-existent settings, but can't already exist and non-existent mixed settings, either all exist or none exist
msetnx key value key value key value ......
Set a new value, and return the old value, if the old value does not exist, return null
getset key value
List (list)
Redis list is a simple list of strings, sorted in the order of insertion. You can add an element to the head (left) or tail (right) of the list. Its bottom layer is actually a linked list.
If the key does not exist, create a new linked list.
If the key already exists, add new content.
If the values are all removed, the corresponding key will also inform you that
the operation of the linked list is extremely efficient in both the head and tail, but if it is performed on the middle element Operation, efficiency is very bleak.
Set the value from left to right
LPUSH key value value ......
Set value from right to left
RPUSH key value value ......
View the value, you can choose according to the subscript, when the end subscript is -1, it is the end
LRANGE key 开始下标 结束下标
Pop the value from the left
LPOP key
Pop value from right
RPOP key
Get the value of a subscript
lindex key index
Get the length
llen key
Delete N values
lrem key n value
Intercept a certain value and assign the intercepted value
ltrim key 开始下标 结束下标
The value popped from the right of the source list is pushed into the target list from the left
rpoplpush 源列表 目标列表
Insert a value in front of a value
linsert key before 基值 插入值
Insert a value after a value
linsert key after 基值 插入值
Set (collection)
Redis Set is an unordered collection of String type, which is implemented through HashTable.
Set a set
sadd key k1 v1 k2 v2 k3 v3
View the value of set
smembers key
Check if there is a key in the set, return 1 if it exists, return 0 if it does not exist
sismember key
Get the number of elements in the set
scard key
Delete an element of the set
srem key value
Randomly select n numbers from the set
srandmember key n
Randomly pop out of the stack, default one, if you write n, then randomly pop out n
spop key n(不写，默认出n个)
Move the value of set1 to set2
smove set1 set2 value
Difference set, elements in set1 but not in set2
sdiff set1 set2
Intersection, elements that exist in both set1 and set2
sinter set1 set2
Union, the set after all elements of set1 and set2 are deduplicated
sunion set1 set2
Hash (hash)
Redis hash is a collection of key-value pairs.
Redis hash is a mapping table of String type field and value. Hash is especially suitable for storing objects.
Similar to the
value of Map<String,Object> in Java , key is the key of redis, and kv is the element of map.
hset key k v
Get the value, first get the element, then get the value in the element
hget key k
Set multiple values
hmset key k v k v k v ......
Get multiple values
hmget key k k k ......
Get all the values
hgetall key
Delete some elements
hdel key k k k ......
Get the number of elements
hlen key
Determine whether an element exists, return 1 if it exists, return 0 if it does not exist
hexists key k
Get the key of all elements
hkeys key
Get the value of all elements
hvals key
If the value of the element is an integer, you can increment an integer
hincrby key k n
If the value of the element is a decimal, you can increase a certain decimal
hincrbyfloat key k n
If an element does not exist, set the value, if there is no set value, return 1 if the set value is successful, and return 0 if the set value fails
hsetnx key k v
Zset (sorted set: ordered collection)
Redis zset is also a collection of String type elements like set, and duplicate members are not allowed.
The difference is that each element is associated with a double type score.
Redis uses scores to sort the members of the set from small to large. The members of zset are unique, but the score (score) can be repeated.
Set value, value is a key-value pair, including score and value
zadd key score value score value score value ......
View value
zrange key 开始下标 结束下标
View value with score
zrange key 开始下标 结束下标 withscores
View the value of a certain score interval
zrangebyscore key 开始分数 结束分数
View the value of a score interval with scores
zrangebyscore key 开始分数 结束分数 withscores
View the value that does not include a certain score range, but does not include the start score or the end score
zrangebyscore key (开始分数 (结束分数
View a certain score interval, and intercept n values from the starting subscript
zrangebyscore key 开始分数 结束分数 limit 开始下标 n
Delete element
zrem key 值
View length
zcard key
Count the number of scores in a certain interval
zcount key 开始分数 结束分数
View the index of the value
zrank key value
View the score of the value
zscore key value
Get the subscript value in reverse order
zrevrank key value
Sort zset in reverse order
zrevrange key 开始下标 结束下标
Get the value of a certain score interval in reverse order
zrevrangebyscore key 开始分数 结束分数
Clear library data (use with caution)
FLUSHDB
Clear all library data (use with caution)
FLUSHALL
Finally, I will provide you with a website of Redis operation manual, you can refer to the Redis command reference