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maven dependency <!--redis--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> <!--<version>2.1.4.RELEASE</version>--> </dependency> <dependency> ...

Data persistence That is, save the data to a permanent storage device (such as disk). 1. redis persistence – two methods I redis Two persistence methods are provided: RDB(Redis DataBase)and AOF(Append Only File). RDB (Redis DataBase): generate snapshots of redis stored data at different time points and store them on disks and oth ...

Query all employee information.Query the number, name and position of each employee.Query all department information.Query all department numbers with employees.Query departments and positions with employees.Query the annual salary of all employees.Query the annual salary of all employees (use alias).Query the annual salary of all employees ((m ...

1. Key objects The connection object -- com.mysql.jdbc.JDBC4Connection contains all configuration parameters about mysql. The setting method is set in the form of parameters attached to the url preparedStatement object -- com.mysql.jdbc.ServerPreparedStatement 2. Data result set reading method There are three types: One is in the form ...

MySQL34 homework questions 1. Name of the person who gets the highest salary in each department mysql> select e.ename,t.* from emp e join (select deptno,max(sal) as maxsal from emp group by deptno) t on t.deptno = e.deptno and t.maxsal = e.sal; +-------+--------+---------+ | ename | deptno | maxsal | +-------+--------+---------+ | BLAKE | ...

🔰 Learning video 🔰 ActiveMQ tutorial (MQ messaging middleware quick start) Number of episodes: 48-57 🔰 Learning maxims 🔰 If you don't practice boxing, you'll end up empty; If the foundation is not strong, the earth will shake. 🔶 Restore the default configuration file of ActiveMQ to facilitate subsequent testing Step 1: d ...

1, MySQL database MySQL database notes 2, mongodb database 1, Introduction to mongodb Non relational database is a document structure, json (Dictionary Plus list), which stores large dataImmune to sql injection statement attacks. The simplest database.There are multiple libraries in mongodb. There are multiple collections in the library, an ...

1, Understand MySQL master-slave replication 1. Supported replication types STATEMENT: STATEMENT based replication. Execute sql statements on the server and the same statements on the slave server. mysql adopts STATEMENT based replication by default, with high execution efficiency. ROW: ROW based replication. Copy the changed content inst ...

1, OpeningRedis, as a general cache model, is very popular because of its high performance. Redis version 2.x only supports stand-alone mode, and the cluster mode has been introduced since version 3.0.Redis's Java ecological clients include Jedis, Redisson and lattice. Different clients have different capabilities and use methods. This paper ma ...

catalogue 1, Overview of master-slave replication and separation of read and write 1. What is read write separation? 2. Why separate reading and writing? 3. When should I separate reading from writing? 4. Master-slave replication and read-write separation 5. Replication types supported by mysq 6. Working process of master-slave replicati ...