如何创建存储过程以获取 SQL Server 2008 中上一列条目的值？

Question

数据库表：UserTime

UserTimeId int(pk)
LoginStatus nvarchar

LoginStatus只存储两条信息：In和Out

例如：

UserTimeId    LoginStatus
--------------------------
    1           In
    2           Out
    3           In
    4           Out   

我想创建一个存储过程来检查上一列的LoginStatus 的值是多少。

在 C# 代码中我想这样实现它：

if (StoredProcedureCheckLoginStatus='In')
{
   dothis...
}
else 
{
   do this....
}

Answer 1

使用 CTE。附样本：

WITH CTE as (
   SELECT 
     RN = ROW_NUMBER() OVER (ORDER BY EmployeeID),
     * 
   FROM HumanResources.Employee
 )
 SELECT
   [Previous Row].*,
   [Current Row].*,
   [Next Row].*
 FROM CTE [Current Row]
 LEFT JOIN CTE [Previous Row] ON 
   [Previous Row].RN = [Current Row].RN - 1
 LEFT JOIN CTE [Next Row] ON 
   [Next Row].RN = [Current Row].RN + 1
 WHERE
       [Current Row].EmployeeID = 5