MyBatis main configuration file mybatis-config.xml

mybatis-config.xmlYes MyBatisThe main configuration file is used to configure MvBatis data source and attribute information
Note: Tags must be written in order, otherwise an error will be reported

1.properties tag

Define key-value pairs

<properties>
    <property name="Test_url" value="jdbc:mysql://localhost:3306/school?useSSL=false"/>
</properties>

Reference properties file Create new file
in resourcesfolderjdbc.properties

Test_driver=com.mysql.jdbc.Driver
Test_url=jdbc:mysql://localhost:3306/school?useSSL=false
Test_username=root
Test_password=root

propertiesresourceReference jdbc.propertiesfiles in tags

<properties resource="jdbc.properties"></properties>

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2.settings tag

Set MyBatisjob properties

<settings>
    <!-- 启用二级缓存 -->
    <setting name="cacheEnabled" value="true"/>
    <!-- 启用懒加载 -->
    <setting name="lazyLoadingEnabled" value="true"/>
    <!-- ...... -->
</settings>

3.typeAliases tag

Give the entity class an alias. You can use the alias directly in the mapping file instead of the fully qualified name of the entity class.

<typeAliases>
    <typeAlias type="com.swkj.pojo.Student" alias="Student"></typeAlias>
</typeAliases>

4.plugins tag

Configure myBatis plug-in

<plugins>
    <plugin interceptor=""></plugin>
</plugins>

5.environments tag

environmentsConfigure database connection information in

<!-- 在environments中可以定义多个environment，每个environment可以定义一套连接配置 -->
<!-- default属性用来指定使用哪个environment -->
<environments default="Test">
    <environment id="Test">
        <!-- transactionManager用于配置数据库管理方式 -->
        <!--
            type 用于指定事务管理的方式
            type="JDBC" 可以进行事务的提交和回滚操作
            type="MANAGED" 依赖容器完成事务管理，本身不进行事务的提交和回滚操作
        -->
        <transactionManager type="JDBC"></transactionManager>
        <!-- dataSource配置数据库连接信息 POOLED|UNPOOLED|JDNI -->
        <dataSource type="POOLED">
            <property name="driver" value="${Test_driver}"/>
            <!-- characterEncoding=utf-8&-->
            <property name="url" value="${Test_url}"/>
            <property name="username" value="${Test_username}"/>
            <property name="password" value="${Test_password}"/>
        </dataSource>
    </environment>
    <environment id="oracle">
        <transactionManager type=""></transactionManager>
        <dataSource type=""></dataSource>
    </environment>
</environments>

5.mappers tag

mappers 1. Used to load mapping files 2. Used to load DAO annotations

<mappers>
    <mapper resource="mappers/StudentMapper.xml"></mapper>
</mappers>