MySQL MySQL选择带有限制的结果总和
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MySQL select SUM of results with a LIMIT
提问by PotatoFro
I have a table full of items and prices for said items. I would like to grab the SUM of the 3 highest priced items.
我有一张桌子，里面装满了物品和上述物品的价格。我想获取 3 个最高价商品的总和。
I thought perhaps SELECT SUM(items.price) FROM items ORDER BY items.price LIMIT 3but that does not seem to do the trick. Is this possible? Thanks!
我想也许SELECT SUM(items.price) FROM items ORDER BY items.price LIMIT 3但那似乎并没有做到这一点。这可能吗？谢谢！
回答by KernelM
select sum(price) from (select items.price from items order by items.price desc limit 3) as subt;
回答by ScottJShea
LIMITaffects the number of rows returned by the query and SUM only returns one. Based on this threadyou might want to try:
LIMIT影响查询返回的行数，SUM 只返回一。基于此线程，您可能想尝试：
SELECT sum(price)
FROM (SELECT price
FROM items
ORDER BY price DESC
LIMIT 3
) AS subquery;
回答by johnshen64
Use a subquery or something like that. Just an idea, as I have not tested the actual query.
使用子查询或类似的东西。只是一个想法，因为我还没有测试过实际的查询。
SELECT SUM(items.price) from (select price FROM items ORDER BY items.price LIMIT 3)
回答by Dave Halter
Just use a sub-select:
只需使用子选择：
select sum(prices) from (SELECT SUM(items.price) FROM items ORDER BY items.price LIMIT 3) as prices
回答by Mare
I haven't tested this and I just wrote it on my memory. You could try something like:
我没有测试过这个，我只是把它写在我的记忆中。你可以尝试这样的事情：
SELECT * AS total FROM items ORDER BY price DESC
SELECT SUM(price) FROM total LIMIT 3;
Edit: I was slow
编辑：我很慢
