事务

事务异常

解决方法

一般将@transactional加在多次修改业务层的方法上

事务属性—回滚

事务属性—传播行为

记录修改事务的日志

@Transactional默认情况下是Required需要事务的，
因为delete中有一个事务了，
因此这个事务就会加到Log里的Transactional中去
因此程序中就只有一个事务
导致Log中的事务也会回滚，
最终删除部门和部门下的员工这个操作就没有保存下来

解决方法

小结

DeptLog

package com.itheima.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.time.LocalDateTime;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class DeptLog {
    private Integer id;
    private LocalDateTime createTime;
    private String description;
}

DeptLogService

package com.itheima.service;

import com.itheima.pojo.DeptLog;

public interface DeptLogService {

    void insert(DeptLog deptLog);
}

DeptLogServiceImpl

package com.itheima.service.impl;

import com.itheima.mapper.DeptLogMapper;
import com.itheima.pojo.DeptLog;
import com.itheima.service.DeptLogService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

@Service
public class DeptLogServiceImpl implements DeptLogService {

    @Autowired
    private DeptLogMapper deptLogMapper;

    @Transactional(propagation = Propagation.REQUIRES_NEW)
    @Override
    public void insert(DeptLog deptLog) {
        deptLogMapper.insert(deptLog);
    }
}

DeptLogMapper

package com.itheima.mapper;

import com.itheima.pojo.DeptLog;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface DeptLogMapper {

    @Insert("insert into dept_log(create_time,description) values(#{createTime}, #{description})")
    void insert(DeptLog log);

}