SQL查询某城市某商品最低价的店铺

Question

我有这个table

(城市,storeID,itemID,价格)

我需要为每个城市 return itemID storeID 以及商品的最低价格和最低价格本身 ( city,itemID,storeIDmin,minprice)。

有人可以帮我解决这个问题吗？

谢谢！

Answer 1

您可以使用相关子查询来解决这个问题：

select t.*
from t
where t.price = (select min(t2.price) from t t2 where t2.itemId = t.itemId);

Answer 2

我用 Join 和 Subquery 解决了这个问题（如果你在 oracle DB 上工作，也可以使用“WITH AS”子句）：

SELECT table1.city, table1.itemID, table1.storeID as storeIDmin, subquery.min_price 
FROM table1
JOIN (select city, itemID, min(price) as min_price from table1 
group by city,itemID) AS subquery
ON table1.city = subquery.city
AND table1.itemID = subqueryitemID
AND table1.price = 
subquery.min_price

结果例如：

+------+---------+--------+-------+
| city | storeID | itemID | price |
+------+---------+--------+-------+
|    1 |       1 |      1 |    70 |
|    1 |       2 |      1 |    60 |
|    2 |       1 |      1 |   100 |
|    2 |       1 |      2 |    90 |
|    2 |       2 |      1 |    88 |
|    3 |       1 |      1 |    70 |
+------+---------+--------+-------+

结果：

+------+--------+----------+-------+
| city | itemID | storeMin | price |
+------+--------+----------+-------+
|    2 |      1 |        1 |   88 |
|    3 |      1 |        1 |    70 |
|    2 |      2 |        1 |    90 |
|    1 |      1 |        2 |    60 |
+------+--------+----------+-------+

SQL查询某城市某商品最低价的店铺

SQL query for the store with the minimum price of an item in the city

sql

subquery