mybatis - CRUD操作

        <insert id="addUser">
            insert into t_user values(null,'张三','123456')
        insert>




        <delete id="deleteUserById">
            delete from t_user where id = 3
        delete>
    
        <update id="updateUser">
            update t_user set username = '王五' where id = 1
        update>




       <select id="getAllUser" resultType="user">
            select * from t_user
       select>


        <select id="getUser" resultType="user">
            select * from t_user where id = 1
        select>

public interface UserMapper {

    int addUser();

    int deleteUserById();

    int updateUser();

    List<User> getAllUser();

    User getUser();
}

 <dependency>
            <groupId>log4jgroupId>
            <artifactId>log4jartifactId>
            <version>1.2.17version>
        dependency>

 version="1.0" encoding="UTF-8" ?>

<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
    <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
        <param name="Encoding" value="UTF-8" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m (%F:%L) \n" />
        layout>
    appender>
    <logger name="java.sql">
        <level value="debug" />
    logger>
    <logger name="org.apache.ibatis">
        <level value="info" />
    logger>
    <root>
        <level value="debug" />
        <appender-ref ref="STDOUT" />
    root>
log4j:configuration>

public class SQLSessionUtils {

    public static SqlSession getSqlSession() {
        SqlSession sqlSession = null;
        try {
            InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
            // openSession(true)  设置为自动提交事务
            sqlSession = factory.openSession(true);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return sqlSession;
    }
}