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1, Redis overview: Redis: it is a persistent single process and single thread key value type cache system. Similar to memcached, it supports relatively more stored value types, including string (string), list (list), set (set) zset(sorted set -- ordered set) and hashes (hash type). These data types all support push/pop, add/remove, intersectio ...

1, Master slave replication concept Master slave replication refers to copying data from one Redis server to other Redis servers. The former is called the master node (master/leader), which is called slave / follower; Data replication is unidirectional and can only be from master node to slave node. Master mainly writes, Slave mainly reads. By ...

What is generics As a literal meaning, a generalized type means that a specific type cannot be determined during encoding. A placeholder (uppercase, English is recommended) needs to be used first. When running, a specific type is passed in to replace this generic tag Why do I need generics Pseudo demand Suppose we need a list to store Strin ...

Project scenario: Spring boot project write off card secret recharge in concurrent test, a card secret is successfully recharged repeatedly Problem Description: The first time I wrote, I didn't consider so much, so I added several logic to verify the card secret status in the business layer. As long as the card secret status is OK, I can ...

Lua scripts quick start Lua is case sensitive premise After Lua is installed on this machine, the installation steps of lua can be completed Basics notes -- This is a single line comment -- [[ This is a multiline comment This is a multiline comment -- ]] Reserved keywords Reserved keyword document address variable Type when ...

introduction Yes NET, we can use interlocked Compareexchange to implement CAS (Compare And Swap) operation. In the distributed scenario, we often use redis. Recently, a wechat game project before the change was run on a single machine. Some data storage is based on memory and directly based on object operation. Recently, redis is introduced to ...

01... Getting started with redis caching brief introduction background In our current project architecture, the Web server (Tomcat) and database are basically deployed independently and monopolize the server resources. With the growth of the number of users, concurrent reading and writing to the database will increase the pressure on dat ...

SET key2 value2 OK MGET key1 key2 key3 # returns a list "value1""value2"(nil) MSET key1 value1 key2 value2 MGET key1 key2 "value1""value2" #### ⑤ , expiration, and SET command extensions Yes key Set the expiration time, and the expiration time will be automatically deleted. This function is often used to control the expiration time ...

Function [#]( ) Ensure complete data transmission Redis distributed lock implementation source code explanation [#]( ) Graphic explanation [#]( ) Step [#]( ) Distributed locks meet two conditions: one is the lock with effective time, and the other is high-performance unlockingredis commands setnx (set if not exist) and setex (set exp ...

1. Introduction to redis Basics 1.1 redis is a high-performance key value cache database, 1. Support data persistence 2. Rich data types 3. Atomic operation 1.2 role of redis 1. Provide cache service 2. For distributed locks 3. Used for message queuing (not the advantage of redis) 1.3 why Redis The traditional application of Mysql bas ...