Hibernate之多表查询

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原生SQL多表查询
1.交叉连接(笛卡尔积)
select * from A, B
2.内连接
(1)隐式内连接
select * from A, B where b.aid = a.id
(2)显示内连接
select * from A inner join B on b.aid = a.id
3.外链接
(1)左外连接
select * from A left [outer] join B on b.aid = a.id
(2)右外连接
select * from A right [outer] join B on b.aid = a.id  
HQL多表查询
1.内连接(迫切)
from Customer c inner join c.linkMans
from Customer c inner join fetch c.linkMans
2.外链接
(1)左外连接(迫切)
from Customer c left join fetch c.linkMans
(2)右外连接(迫切)
from Customer c right join fetch c.linkMans

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