Mybatis如何批量导入数据？三种方法详解

2021-08-07 15:53:55 浏览数 (5252)

1. 循环插入

mapper.xml：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.buhe.demo.mapper.StudentMapper">
  <insert id="insert" parameterType="Student">
    INSERT INTO tb_student (name, age, phone, address, class_id) VALUES (#{name},#{age},#{phone},#{address},#{classId})
  </insert>
</mapper>

mapper接口：

public interface StudentMapper {
    int insert(Student student);
}

测试代码：

@SpringBootTest
class DemoApplicationTests {
	@Resource
	private StudentMapper studentMapper;

	@Test
	public void testInsert(){
		//数据生成
		List<Student> studentList = createData(100);

		//循环插入
		long start = System.currentTimeMillis();
		studentList.stream().forEach(student -> studentMapper.insert(student));
		System.out.println(System.currentTimeMillis() - start);
	}

	private List<Student> createData(int size){
		List<Student> studentList = new ArrayList<>();
		Student student;
		for(int i = 0; i < size; i++){
			student = new Student();
			student.setName("小王" + i);
			student.setAge(18);
			student.setClassId(1);
			student.setPhone("1585xxxx669");
			student.setAddress("未知");
			studentList.add(student);
		}

		return studentList;
	}
}

2. foreach标签

mapper.xml：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.buhe.demo.mapper.StudentMapper">
  <insert id="insert" parameterType="Student">
    INSERT INTO tb_student (name, age, phone, address, class_id) VALUES (#{name},#{age},#{phone},#{address},#{classId})
  </insert>

  <insert id="insertBatch">
    INSERT INTO tb_student (name, age, phone, address, class_id) VALUES
    <foreach collection="list" separator="," item="item">
        (#{item.name},#{item.age},#{item.phone},#{item.address},#{item.classId})
    </foreach>
  </insert>
</mapper>

mapper接口：

public interface StudentMapper {
    int insert(Student student);

    int insertBatch(List<Student> studentList);
}

测试代码：

@SpringBootTest
class DemoApplicationTests {
	@Resource
	private StudentMapper studentMapper;

	@Test
	public void testInsertByForeachTag(){
		//数据生成
		List<Student> studentList = createData(100);

		//使用foreach标签，拼接SQL插入
		long start = System.currentTimeMillis();
		studentMapper.insertBatch(studentList);
		System.out.println(System.currentTimeMillis() - start);
	}


	private List<Student> createData(int size){
		List<Student> studentList = new ArrayList<>();
		Student student;
		for(int i = 0; i < size; i++){
			student = new Student();
			student.setName("小王" + i);
			student.setAge(18);
			student.setClassId(1);
			student.setPhone("1585xxxx669");
			student.setAddress("未知");
			studentList.add(student);
		}

		return studentList;
	}
}

3. 批处理

测试代码：

@SpringBootTest
class DemoApplicationTests {
	@Autowired
	private SqlSessionFactory sqlSessionFactory;

	@Test
	public void testInsertBatch(){
		//数据生成
		List<Student> studentList = createData(100);

                //使用批处理
		long start = System.currentTimeMillis();
		SqlSession sqlSession = sqlSessionFactory.openSession(ExecutorType.BATCH,false);
		StudentMapper studentMapperNew = sqlSession.getMapper(StudentMapper.class);
		studentList.stream().forEach(student -> studentMapperNew.insert(student));
		sqlSession.commit();
		sqlSession.clearCache();
		System.out.println(System.currentTimeMillis() - start);
	}

	private List<Student> createData(int size){
		List<Student> studentList = new ArrayList<>();
		Student student;
		for(int i = 0; i < size; i++){
			student = new Student();
			student.setName("小王" + i);
			student.setAge(18);
			student.setClassId(1);
			student.setPhone("1585xxxx669");
			student.setAddress("未知");
			studentList.add(student);
		}

		return studentList;
	}
}

三种方式的对比

MySQL服务器版本：5.6.4

其他依赖版本如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.4.4</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.buhe</groupId>
	<artifactId>demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>demo</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>1.8</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>

		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>5.1.41</version>
		</dependency>
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>1.3.1</version>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>

		<resources>
			<resource>
				<directory>src/main/java</directory>
				<includes>
					<include>**/*.xml</include>
				</includes>
			</resource>
		</resources>
	</build>

</project>

三种插入方式在不同数据量下的表现，测试结果：

插入方式 10条 100条 500条 1000条
循环插入 496ms 3330ms 15584ms 33755ms
foreach标签 268ms 366ms 392ms 684ms
批处理 222ms 244ms 364ms 426ms

三种方式中，批处理的方式效率是最高的，尤其是在数据量大的情况下尤为明显。

其次是foreach标签，foreach标签是通过拼接SQL语句的方式完成批量操作的。但是当拼接的SQL过多，导致SQL大小超过了MySQL服务器中max_allowed_packet变量的值时，会导致操作失败，抛出PacketTooBigException异常。

最后是循环插入的方式，这种方式在数据量小的时候可以使用，在数据量大的情况下效率要低很多。

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