SqlSession seems not trigger batch operation unless I use @Transactional

[shin8085]

MyBatis version

3.5.9

Database vendor and version

SQLServer 2019 15.0.4198.2

Test case or example project

@Component
public class DataTest {
    @Resource
    private SqlSessionFactory sqlSessionFactory;

//    @Transactional
    public void add(List<Data> itemList) {
        SqlSession session = sqlSessionFactory.openSession(ExecutorType.BATCH, false);
        DataMappermapper = session.getMapper(DataMapper.class);
        for (int i = 0; i < itemList.size(); i++) {
            mapper.insert(itemList.get(i));
        }
        session.commit();
        session.clearCache();
    }
}
class DataSyncApplicationTests {

    @Resource
    DataTest dataTest;

    @Test
    void contextLoads() throws Exception {
        StopWatch stopWatch=new StopWatch();
        List<Data> list=new ArrayList<>();
        for(int i=0;i<50000;i++){
            Data data=new Data();
            data.setId("test:"+i);
            data.setRemark("new");
            data.setResult("new");
            data.setClueId("nddd");
            data.setOwnerName("ffff");
            data.setAudioUrl("fffff");
            list.add(data);
        }
        stopWatch.start();
        dataTest.add(list); //invoke
        stopWatch.stop();
        System.out.println(stopWatch.getLastTaskTimeMillis());
    }
}

Steps to reproduce

When I run this code it took me 42091ms, but if I add @Transactional to my method before run it that it's only spend 4930ms.

Expected result

take less time and don't neet @Transactional, there seems to have been some transaction operations in SqlSession but I don't sure it is work

Actual result

it need @Transactional

[codeysk]

I also had this problem and found that the autoCommit value in the Connection obtained through the proxy object was still true and needed to be manually set to false

[harawata]

Please read the mybatis-spring documentation. https://mybatis.org/spring/ A sample code with BATCH executor type and its limitation is explained in this page. https://mybatis.org/spring/sqlsession.html

[harawata]

By the way, you still need @Transactional to perform batch insert. Without @Transactional, a new session will be created for each INSERT.

[DaZuiZui]

SqlSession will not trigger batching automatically because there is no transaction context.