SQL查询返回的列的值大于某个最小值（取决于类别）的行？

Question

例如，如果我有这两个表：

表格1：

item       category     rating
------     --------     ------
table      furniture      6
chair      furniture      5
sofa       furniture      7
bed        furniture      4
apple      food           7
banana     food           6
spinach    food           9
almonds    food           8
happiness  feeling        7
compassion feeling        6
love       feeling        8
admiration feeling        7

和表2：

category     minimum_rating
--------     --------------
furniture          6 
food               8
feeling            7

并考虑到每个类别的minimum_rating值每个月都会修改，因此它会发生变化...我将如何相对于table2查询table1，以便它将该项的该类别的minimum_rating值取回仅表1中那些评级等于或高于最小评级的项目？ 在这种情况下，查询将返回：

item       category     rating
------     --------     ------
table      furniture      6
sofa       furniture      7
spinach    food           9
almonds    food           8
happiness  feeling        7
love       feeling        8
admiration feeling        7

非常感谢您的宝贵意见！

Answer 1

我认为您需要在两个表上都JOIN ，如下所示。 您可能还可以说t1.rating = t2.minimum_rating

select t1.*
from table1 t1 join table2 t2 on t1.category = t2.category
where t1.rating >= t2.minimum_rating;

Answer 2

一个简单的联接就可以完成这项工作：

Select a.* from table1 as a
 inner join table2 as b on a.furniture = b.furniture and a.rating >=     b.minimum_rating;