Programmer Group

1, Preface: In the era of big data, the concurrency of network requests leads to huge database I/O overhead. Therefore, in order to alleviate the pressure of the database, caching technology is essential. Among them, redis is basically one of the server's caching services. Although caching technology is very easy to use, there will be a variet ...

1. Second kill code (most low implementation): //Open transaction @Transactional(rollbackFor = Exception.class) public BaseResponse<?> startSeckillWithLock(Long id, Long userId) { try { return seckill(id, userId); } catch (Exception e) { throw e; } finally { } } p ...

Introduction: in the project, I met the need to merge MySQL database tables. In the process of merging, I should skip the existing records, because the primary key was not set in the initial stage of table design. Finally, I realized the requirements through MySQL's not exists statement. By the way, I explored the multi table connection in MySQ ...

Installing Oracle on Linux requires some preparation, such as dependency packages, groups and users, kernel parameters, resource constraints, directories, environment variables, and so on. This series of articles is to share the author's practical records when he first came into contact with and studied Linux. It mainly includes some theo ...

Learning content: learn the Spring framework (Day50) 1,Spring JDBC 2. Mysql transaction 3. Mysql trigger 1,Spring JDBC (1) The required jar package is used for database connection using Hikaricp connection pool mysql-connector-java.jar HikariCP.jar spring-jdbc.jar (2) Configure the data source file db.properties, and set the time zone for ...

catalogue Less41 Less42 Less43 Less44 Less45 Less46 Less47 Less48 Less49 Less50 Less41 This level is similar to Less40. First find the closure through Boolean blind injection, and then stack and inject recklessly. Find closure: http://192.168.101.16/sqli-labs-master/Less-41/?id=1   There are query results http://192.168.10 ...

Have you ever seen such a sentence: "The people I love also love me. It's a miracle for me." Or: "Life without friends is like life without sunshine." Or this: "I will hold you, pull you and save you. I won't let go, but you want me to hold you, you know?" Are some very interesting sentences, how to get these ...

spring implements transaction management Transaction is an important part of enterprise application oriented to relational database (RDBMS), which is used to ensure the integrity and consistency of data. ACID attribute of the transaction Atomicity: a transaction is an inseparable unit of work, and the actions included in the transaction are ...

Redis profile INCLUDES redis can load multiple configuration files Application scenario: When you have multiple redis servers, you can select a public redis configuration file and set some differentiated configurations on each redis server, which can be realized by using include in the configuration file ########################## ...

1. Collection overview 1.1 what is a collection? What's the usage? An array is actually a collection. A collection is actually a container. Can be used to accommodate other types of data. Why are collections used more in development? A collection is a container and a carrier that can hold multiple objects at a time. In the actual development ...