如何使用MYSQL LIMIT每人
所以我有一个场景，有 1-8 个人，我需要查询每人最多 3 件他们“喜欢”的东西。我已将查询设置为，
SELECT liked FROM likeTable WHERE uid IN (uid1,uid2,uid3,uid4) LIMIT 12
但显然，当我对 uid1 有 12 个“喜欢”时，这可能会停止，其余的为 0。我读到了一个可能的解决方案，例如使用 UNION ALL...
(SELECT liked FROM likeTable WHERE uid = uid1 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid2 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid3 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid4 LIMIT 3)
我将能够实现这是通过使用 forloop 在 php 中创建 sql 查询字符串来实现的，但这是查询数据的有效方法吗？
注意：我并不真正关心检索“喜欢”的顺序，尽管如果我可以添加一个 ORDER BY likeID DESC（这是我的自动增量列），那就太好了，
谢谢！
So I have a scenario where there are 1-8 people that i need to query up to 3 things they "liked" per person. I have the query set up as
SELECT liked FROM likeTable WHERE uid IN (uid1,uid2,uid3,uid4) LIMIT 12
but obviously this can potentially stop when i have 12 "likes" for uid1, leaving the rest at 0. I read a possible solution as using UNION ALL for example...
(SELECT liked FROM likeTable WHERE uid = uid1 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid2 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid3 LIMIT 3)
UNION ALL
(SELECT liked FROM likeTable WHERE uid = uid4 LIMIT 3)
And i would be able to achieve this by making the sql query string in php with a forloop, but is this an efficient way of querying my data?
note: I don't really care about the order in which the "liked" is retrieved, although it would be nice if i could add an ORDER BY likeID DESC, which is my autoincrementing column
Thanks!
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对于少量（不是数百，我想说）类别（用户），只需使用联合解决方案。
我是否能够通过使用 forloop 在 php 中创建 sql 查询字符串来实现此目的，但是这是查询数据的有效方法吗？
绝对是的！除非你一次性查询了数百个用户。对于1-8人来说，这只是完美的解决方案！
For small number (not hundreds, I would say) of categories (users), just use the union solution.
And would I be able to achieve this by making the sql query string in php with a forloop, but is this an efficient way of querying my data?
Definitelly yes! Unless you query hundreds of users in one go. For 1-8 people, it is just perfect solution!