【弄nèng - 化繁为简】@Transactional同一事务中更新立刻能查到

@Transactional，在一个事务中更新数据，在查询能查询到新数据

同一个类中

在一个事务中更新之后再查询能查询到最新的数据，毋庸置疑。
代码

    @Autowired
    private TestMapper testMapper;

    @Transactional
    public void testTransactional() {
        System.out.println("1.====:" + testMapper.selectById(1).toString());
        updateTestById("司马缸5");
        System.out.println("2.====:" + testMapper.selectById(1).toString());
    }
    
	public void updateTestById(String name) {
        TestEntity entity = new TestEntity();
        entity.setId(1);
        entity.setName(name);
        testMapper.updateById(entity);
    }

执行testTransactional()
输出

不同的类中

A更新，B查询，也能查询到新数据，因为B加入到A的事务中了。此时如果B中出现异常,AB中的操作都会回滚

代码

@Service
public class TestServiceImpl extends ServiceImpl<TestMapper, TestEntity> implements ITestService {

    private static Map<String, String> map = Maps.newHashMap();
    @Autowired
    private TestMapper testMapper;

    @Autowired
    private TestServiceImpl2 testServiceImpl2;

    @Transactional
    public void testTransactional() {
        System.out.println("1.====:" + testMapper.selectById(2));

        updateTestById("司马缸2");

        System.out.println("2.====:" + testMapper.selectById(2));

        System.out.println("3.====:" + testServiceImpl2.get());
    }

    public void updateTestById(String name) {
        TestEntity entity = new TestEntity();
        entity.setId(1);
        entity.setName(name);
        testMapper.updateById(entity);
    }
}



@Service
public class TestServiceImpl2 extends ServiceImpl<TestMapper, TestEntity> implements ITestService {

    @Autowired
    private TestMapper testMapper;

//    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public TestEntity get() {
        TestEntity entity = testMapper.selectById(2);
        return entity;
    }
}

执行testTransactional()
输出