今天使用JPA自定义了一个删除方法deleteByUserIdAndCommentId发现并没有删除掉对应的数据，只执行了查询语句
Hibernate: select good0_.id as id1_6_, good0_.commentId as commenti2_6_, good0_.userId as userid3_6_ from tbl_good good0_ where good0_.userId=? and good0_.commentId=?
在删除方法前加注解@Transactional即可
再次执行时会正常执行
Hibernate: select good0_.id as id1_6_, good0_.commentId as commenti2_6_, good0_.userId as userid3_6_ from tbl_good good0_ where good0_.userId=? and good0_.commentId=? Hibernate: delete from tbl_good where id=? Hibernate: select comment0_.id as id1_3_0_, comment0_.articleId as articlei2_3_0_, comment0_.ccomment as ccomment3_3_0_, comment0_.goodNum as goodnum4_3_0_, comment0_.userId as userid5_3_0_, comment0_.userType as usertype6_3_0_ from tbl_comment comment0_ where comment0_.id=?
今天写新模块的一个删除功能，测试的时候出了几个问题。
原代码：
@Query("delete from PrivateMessageEntity ae " +
"where ((ae.sendId=?1 and ae.receiveId=?2)or(ae.sendId=?2 and ae.receiveId=?1)) " +
"and ae.deleted=?3")
int deleteDetailPrivateLetterList(Long sendId, Long receiveId, Boolean deleted);
于是乎我把该hql语句转成sql语句去navicat上执行了一遍，报错显示sql语法有误。
根据指示的错误起始位置，怀疑是别名问题，查了一下，sql的delete在使用别名时 在 delete 与from 之间的表别名不可省略
正确sql如下：
delete a.* from tb_table a where a.id=1;
修改之后的代码如下：
@Query(value = "delete ae.* from tb_zone_private_message ae " +
"where ((ae.sendId=?1 and ae.receiveId=?2)or(ae.sendId=?2 and ae.receiveId=?1)) " +
"and ae.deleted=?3",nativeQuery = true)
int deleteDetailPrivateLetterList(Long sendId, Long receiveId, Boolean deleted);
这下看起来没问题了，测试了一遍又报错了。
复制报错信息又去查了一下，发现对于执行update和delete语句需要添加@Modifying注解。
修改后代码如下：
@Modifying
@Query(value = "delete ae.* from tb_zone_private_message ae " +
"where ((ae.sendId=?1 and ae.receiveId=?2)or(ae.sendId=?2 and ae.receiveId=?1)) " +
"and ae.deleted=?3",nativeQuery = true)
@Transactional
int deleteDetailPrivateLetterList(Long sendId, Long receiveId, Boolean deleted);
测试一遍，删除成功。
以上为个人经验，希望能给大家一个参考，也希望大家多多支持。
