hibernate 多对多 中间表查询
- 作者: 玉臂匠
- 来源: 51数据库
- 2020-11-24
为什么不配置成多对多的关系呢
user实体
@ManyToMany(cascade = { CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY)
@JoinTable(name="T_USER_ROLE", joinColumns={@JoinColumn(name="userid")},
inverseJoinColumns={@JoinColumn(name="roleid")})
private Set roles;
------------------------------------------------
role实体
@ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY, mappedBy="roles")
private Set users;
select * from B where B.bid=(select bid from C where C.aid=A.aid);
再看看别人怎么说的。
user实体
@ManyToMany(cascade = { CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY)
@JoinTable(name="T_USER_ROLE", joinColumns={@JoinColumn(name="userid")},
inverseJoinColumns={@JoinColumn(name="roleid")})
private Set
------------------------------------------------
role实体
@ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE },
fetch = FetchType.LAZY, mappedBy="roles")
private Set
select * from B where B.bid=(select bid from C where C.aid=A.aid);
再看看别人怎么说的。
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