Sql server 使用交叉选择的Ms-Sql？

我对group by有一些疑问。我还有两个学校Id最低和最高收入。我分组并计算总收入。但我不知道如何使用交叉选择

 RowId    SchoolId  month   maxEarning   minEarning

 1         1        1        1000         900
 2         1        2        2000         300 
 3         1        3        1500         750
 4         2        1        2000         500
 5         2        2        1500         1000
 6         3        1        2000         1000 

答案是

  school id 1 ==> diff second month and first month 2000 - 900 = 1100
  school id 1 ==> diff third month and second month 1500 - 300 = 1200
  school id 2 ==> diff second month and first month 1500 - 500 = 1000
  school id 3 ==> diff first month only 2000

最后我想看到的是：

   RowId    SchoolId  month   maxEarning   minEarning    DiffWithGroup
    1         1        1        1000         900         1000
    2         1        2        2000         300         1100
    3         1        3        1500         750         1200
    4         2        1        2000         500         2000
    5         2        2        1500         1000        1000
    6         3        1        2000         1000        2000

---

如果您的SQL Server版本支持，

LAG

分析函数是一个选项：

SELECT
    RowId, SchoolId, month, maxEarning, minEarning,
    maxEarning - LAG(minEarning, 1, 0) OVER
        (PARTITION BY SchoolId ORDER BY month) AS DiffWithGroup
FROM yourTable
ORDER BY RowId;

---

如果您的SQL Server版本支持，

LAG

分析功能是一个选项：

SELECT
    RowId, SchoolId, month, maxEarning, minEarning,
    maxEarning - LAG(minEarning, 1, 0) OVER
        (PARTITION BY SchoolId ORDER BY month) AS DiffWithGroup
FROM yourTable
ORDER BY RowId;

---

对于SQL Server 2012及更高版本，您可以使用LAG（）

---

对于SQL Server 2012及更高版本，可以使用LAG（）

---

我们可以使用

LAG

函数来执行此操作-

select
    RowId,
    SchoolId,
    month,
    maxEarning,
    minEarning,
    DiffWithGroup = (maxEarning - lag(minEarning,1,0) over(partition by SchoolId order by month))
from YourTableName

---

在此处检查此函数-

我们可以使用

LAG

函数来执行此操作-

select
    RowId,
    SchoolId,
    month,
    maxEarning,
    minEarning,
    DiffWithGroup = (maxEarning - lag(minEarning,1,0) over(partition by SchoolId order by month))
from YourTableName

---

在此处检查此功能-

您使用的是

MySQL

还是

SQL Server

？Microsoft SQL Server到目前为止您尝试了什么？您使用的是

MySQL

还是

SQL Server

？Microsoft SQL Server到目前为止您尝试了什么？