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组查询和前n个记录SQL_Sql_Database - Fatal编程技术网
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组查询和前n个记录SQL

sql database

组查询和前n个记录SQL,sql,database,Sql,Database,如果我有一个表，其中列pid，sid作为主键，列price和color 如何创建一个SQL查询，以获取每个pid（产品ID）中颜色等于绿色的最便宜价格 例如，我有行： (1, 1, 10, "green") (1, 2, 8, "green") (1, 3, 11, "green") (2, 1, 7, "green") (2, 2, 15, "green") (2, 3, 22, "green") (3, 1, 10, "red") (1, 2, 8, "red") (1, 3, 11, "r

如果我有一个表，其中列
pid，sid
作为主键，列
price
和
color

如何创建一个SQL查询，以获取每个
pid
（产品ID）中颜色
等于绿色
的最便宜价格

例如，我有行：


(1, 1, 10, "green")
(1, 2, 8, "green")
(1, 3, 11, "green")
(2, 1, 7, "green")
(2, 2, 15, "green")
(2, 3, 22, "green")
(3, 1, 10, "red")
(1, 2, 8, "red")
(1, 3, 11, "red")


然后我将收到：
（1,2,8）->pid=1
和
（2,1,7）->pid=2
。没有
pid=3
，因为它的颜色是红色

提前谢谢


SELECT pid, min(Price)
from table
Where Color='green'
group by pid


或者如果您想要整行（并且您的sql平台支持排名）

试试这个


SELECT  a.*
FROM    tableName a
            INNER JOIN
            (
                SELECT pid, min(price) minPrice
                FROM    tableName b
            ) c ON a.pid = c.pid AND
                    a.price = c.minprice
WHERE   a.color = 'green'



@用户1613224请查看以下内容：

SELECT  a.*
FROM    tableName a
            INNER JOIN
            (
                SELECT pid, min(price) minPrice
                FROM    tableName b
            ) c ON a.pid = c.pid AND
                    a.price = c.minprice
WHERE   a.color = 'green'