Mybatis插入大量数据效率对比:foreach、SqlSession批量、sql(1),2024年最新怒肝三个月啃完这110道面试题

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public List list = new ArrayList<>();

@Before

public void getList() {

long start = System.currentTimeMillis();

Users user;

for (int i = 1; i <=50000 ; i++) {

user = new Users();

user.setId(i);

user.setName("java");

user.setAge(200);

user.setManagerId(222);

list.add(user);

}

System.out.println("拼装数据 耗时:"+(System.currentTimeMillis()-start));

System.out.println(list.size());

}

@Test

public void batchInsert() {

SqlSession sqlSession = sqlSessionFactory.openSession(ExecutorType.BATCH,false);

UsersMapper mapper = sqlSession.getMapper(UsersMapper.class);

System.out.println("batchInsert 插入开始========");

long start = System.currentTimeMillis();

for (int i = 0; i < list.size(); i++) {

mapper.insert(list.get(i));

if (i%5000==4999) {

sqlSession.flushStatements();

// sqlSession.commit();

// sqlSession.clearCache();

}

}

// sqlSession.commit();

// sqlSession.clearCache();

sqlSession.flushStatements();

System.out.println("SqlSession 批量插入耗时:"+(System.currentTimeMillis()-start));

}

@Test

public void forEachInsert() {

System.out.println("forEachInsert 插入开始========");

long start = System.currentTimeMillis();

for (int i = 0; i < list.size(); i++) {

usersMapper.insert(list.get(i));

}

System.out.println("foreach 插入耗时:"+(System.currentTimeMillis()-start));

}

@Test

public void sqlInsert() {

System.out.println("sql 插入开始========");

long start = System.currentTimeMillis();

usersMapper.sqlInsert(list);

System.out.println("sql 插入耗时:"+(System.currentTimeMillis()-start));

}

//xml批量插入

@Test

public void xmlInsert() {

System.out.println("xmlInsert 批量插入开始========");

long start = System.currentTimeMillis();

usersMapper.xmlBatchInsert(list);

System.out.println("xmlInsert 批量插入耗时:"+(System.currentTimeMillis()-start));

}

}

//sql插入相关类

@Repository

public interface UsersMapper extends BaseMapper {

@InsertProvider(type = UsersProvider.class, method = "insertListSql")

public void sqlInsert(List list);

public void xmlBatchInsert(@Param("list") List list);

}

public class UsersProvider {

public String insertListSql(List list) {

StringBuffer sqlList = new StringBuffer();

sqlList.append(" INSERT INTO users(id,name,age,manager_id) VALUES ");

for (int i = 0; i < list.size() ; i++) {

Users user = list.get(i);

sqlList.append(" (").append(user.getId()).append(",").append("'").append(user.getName()).append("',").append(user.getAge())

.append(",").append(user.getManagerId()).append(")");

if (i < list.size()-1) {

sqlList.append(",");

}

}

return sqlList.toString();

}

}

xml 插入mapper文件

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