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Project construction IDEA creates an empty maven projectIn the parent project POM Add dependencies to XML (mysql driver, mybatis dependency, and junit unit test)Add a sub project to improve the package structure <dependencies> <!-- mysql drive--> <dependency> <groupId>mysql</groupId> ...

Spring Boot learning Official website: https://spring.io/projects/spring-boot#overview file: https://docs.spring.io/spring-boot/docs/2.2.6.RELEASE/reference/html/ Reference video: [crazy God says Java] the latest tutorial of SpringBoot, IDEA version, is easy to understand_ Beep beep beep_ bilibili Project complete reference code: lexi ...

1, What is deferred loading In the development process, we do not always need to load the user's order information when loading the user's information. This is what we call delayed loading. 1. Definition of delayed loading Delayed loading is to load when data is needed, and not when data is not needed. Lazy loading is also called lazy lo ...

Mybatis plus common annotations and plug-ins (II) 1, @ TableName value attribute The name of the entity class is User and the name of the database table is t_user @TableName(value = "t_user") public class User { //... } 2, @ TableId 1. Snowflake algorithm By default, the id column of the database is generated by the strategy based o ...

Delayed loading mechanism of mybatis The meaning of delayed loading: relevant operations will be carried out only when it is used Mybatis supports delayed loading of association Association objects and Collection association collection objects Difference: association usage scenario is a one-to-one association query, and collection is a one t ...

Mybatis environment JDK1.8Mysql5.7maven 3.6.3IDEA review JDBCMysqlJava FoundationMavenJunit SSM framework: the best way to configure files: see the official website documents Mybatis 1. Introduction to Mybatis (October 21, 2020) 1.1 what is Mybatis How to get Mybatis maven warehouse: <!-- https://mvnrepository.com/artifact/org ...

MyBatis Environmental Science: JDK1.8Mysql 5.7maven 3.6.1IDEA Review: JDBCMysqlJava FoundationMavenJunit SSM framework: Configuration file. Best way: see the official website documentation; mybatis - MyBatis 3 | Getting Started 1. Introduction 1.1, What is Mybatis MyBatis is an excellent persistence framework. It supports customizing S ...

1.1 introducing pom dependency When introducing SpringBoot and SpringCloud versions, pay special attention to their compatibility Reference: https://spring.io/projects/spring-cloud <!--introduce springboot Parent project dependency--> <!--Introduce dependency: It can be omitted version Tag to get some reasonable ...

MyBatisPlus MyBatisPlus overview brief introduction MyBatis is meant to simplify JDBC operations! Official website: https://mp.baomidou.com/ MyBatis Plus simplifies MyBatis! characteristic No invasion: it is only enhanced without change, and its introduction will not affect the existing project, which is as smooth as silk L ...

https://mybatis.org/mybatis-3/zh/index.html 1, Mybatis official website definition Mybatis configuration 1. Type aliases Type alias sets an abbreviated name for a Java type. It is only used for XML configuration and is intended to reduce redundant fully qualified class name writing. For example: <typeAliases> <typeAlias alias ...