Redis Operations for Python

Redis

is a high-performance Key-value database, which is a non-relational database. The following three features are available:

• Redis supports data persistence, which saves data in memory on disk and can be loaded again for use when restarting.
• Redis not only supports simple key-value types of data, but also provides storage of data structures such as List,set,zset,hash.
• Redis supports backup of data, that is, Master-slave mode of data backup.

1, Redis installation.

In the cmd command window, enter: Pip install Redis

2, connect Redis.

R = Redis. Redis (host= ' 127.0.0.1 ', password= ' hk139bc&* ', db=1,port=6379)

Description: Host is the IP address, password is the Redis password, DB connection after the use of the database, redis default has 15 databases, port is the port number, the default is 6379

3. Redis Delete and change, for the operation of string type.

1), a new value in the database:

R.set ('qianqian',' handsome!  '# A new value is added to the database. K is Qianqian,value is handsome, the redis inside has this k's words to modify the value, does not have the words to increase the k, and the value

R.set (' Xiehong:qianqian ', ' Handsome! ') #数据库里面新增一个值, if there is a colon inside K, then a folder named after the colon will be generated in the Redis after successful insertion

2), get the value of K

Print (R.get ('xiehong:qianqian')) # Get K is the value of Xiehong:qianqian, the default return result is the binary Print (R.get ('xiehong:qianqian'). Decode ()) # converting binary results to Chinese # The result is:b'\xe5\xb8\x85\xef\xbc\x81' handsome! 

3), delete K and value

R.delete ('xiehong:qianqian')# after deletion, the corresponding K and value are deleted

4), set the expiration time of key

R.setex ('python_123',' hahaha ', ')  #  Set the expiration time of key, the last parameter is the second

5), get all the keys

R.keys ('*xxx*'))# gets all the keys

4, hash type (hash) operation.

The value of a hash type is a nested dictionary.

1), add K and value

R.hset ('Xinxin','New New','1M8 100w Deposit') R.hset ('Xinxin','Red Red','How many lessons can be wasted in the years') R.hset ('Xinxin','Qian','I wish I could walk through you and see the Truth')

The above key is Xinxin,value is the following data, log on to Redis on the operation results of the above code:

2), to obtain value, you need to make a large key and small key to obtain the corresponding value, for example:

Print (R.hget ('xinxin',' new '). Decode ())  # specify big key and small key to get corresponding data # Gets the result:1m8 100w Deposit

3), get all the key and value

Print (R.hgetall ('xinxin'))  # get all the K and V inside

4), delete key

R.hdel ('stu_info','gyx')  # Delete the specified key R.delete ('stu_info')  # Delete entire key

5), set the expiration time of the first key

R.expire ('xinxin'# first key set expiration time

5. Supplementary string Conversion

s=' hehe '# turn the string into binary HWT = b'sdfsdfsdf'  Hwt.decode ()  # Turn the bytes type into a string

Redis Operations for Python