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1, Global command 1. Query key Keys * query all keys and traverse all key values, complexity O(n) 2. Total number of keys dbsize queries the total number of keys and directly obtains the total number of keys variable built in redis. The complexity is O(1) 3. Check whether the key exists exists key returns 1 if it exists and 0 if it does n ...

brief introduction I want to develop a social networking site. Storing friends list on social networking sites has become a big problem in the development process. If I want to save every user's friend information, how should I save it? The user's id corresponds to the friend's id. such a message is a friend relationship map. This relati ...

Redis data type Redis supports five data types: string, hash, list, set and Zset. String (string) As like as two peas, string is the most basic type of redis. You can understand it as a type that is exactly the same as Memcached, and a key corresponds to a value. The string type is binary safe. This means that the redis string can con ...

brief introduction Didn't you write an article earlier An implementation of like function Your article Some problems were also raised at that time, and today we will solve some of them start Let's talk about the background first to avoid the confusion of not reading the previous article Let's talk about the like function. Here we mainly so ...

1. Introduction to MyBatis cache Mybatis supports caching, but without configuration, it only enables the L1 cache by default, and the L2 cache needs to be manually enabled. The L1 cache is only relative to the same SqlSession. That is, for the same transaction, execute the same query method of the same Mapper multiple times. After the fir ...

There are two storage methods in H5 1,window.sessionStorage session storage: Save in memory. The lifecycle is to close the browser window. That is, the data is destroyed when the window is closed. Data can be shared in the same window. 2,window.localStorage local storage: It may be saved in the browser memory or on the hard disk. Perm ...

preface The previous chapters learned the following: Cache manager related abstractionsAnnotations and attributes related to cache operationThe CacheOperation corresponding to the cache operation is related to the CacheOperationSource responsible for resolving the corresponding CacheOperations The above content paves the way for an in-de ...

1. Open remote connection Redis does not support remote connection by default and needs to be opened manually. Enter redis conf Comment out the following bind ing Uncomment and set password (enable password verification) requirepass 123456 Then start redis 2. Jedis Create a normal Maven projectAdd Jedis dependency <dependency& ...

There is no problem logging in different accounts with the same browser, but there may be major problems. The second login will overwrite the token of the first login, resulting in the second login user operating some data of the first login. Here is a solution. 1. Log in to account A in the login window, and then copy the same url to log in t ...

Redis implements distributed caching IDistributedCache,StackExchangeRedis Redis learning tutorial: Windows installs redis and sets the redis service to start automatically: https://blog.csdn.net/qq_40732336/article/details/122653953 Redis Chinese website https://www.redis.net.cn/ Build a Redis cluster in master / slave mode https://blog.cs ...