[英]NHibernate fetch creates right query and then performs N+1
I have three entities, configured as 我有三个实体,配置为
Contact
HasOne(e => e.User).PropertyRef(e => e.Contact).Cascade.All();
User
HasMany(e => e.Requests);
References(e => e.Contact);
Request
References(e => e.User);
And then I do query like this: 然后我这样查询:
CurrentSession.Query<Request>()
.Fetch(x => x.User)
.ThenFetch(x => x.Contact)
.ToList();
And it looks like Fetch is working, because in first select I see all the tables joined (omitted other fields for brevity): 看起来Fetch正在运行,因为在第一个选择中,我看到了所有连接的表(为简洁起见,省略了其他字段):
SELECT request0_.Id as Id128_0_,
user1_.Id as Id131_1_,
contact2_.Id as Id77_2_,
FROM requests request0_
left outer join users user1_
on request0_.user_id = user1_.Id
left outer join contacts contact2_
on user1_.contact_id = contact2_.Id
And then follow N+1 selects for some reason, I can't understand and have no ideas how to troubleshoot the issue: 然后由于某些原因遵循N + 1选择,我不明白,也不知道如何解决此问题:
SELECT user0_.Id as Id131_0_,
FROM users user0_
WHERE user0_.contact_id = 200 /* @p0 - contact_id */
目前,这是NHibernate中的错误 。
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