在存储过程中循环数据表

Question

我有一个存储过程,只需单击按钮就可以输入超过8000行,用于关闭员工的每日出勤率.

我计划将输入作为数据表发送到存储过程,而不是每次都逐行发送

我设法创建一个表类型用户定义类型,并使用具有该用户定义类型的参数作为输入参数

  USE [ATCHRM.MDF]
GO

/****** Object:  UserDefinedTableType [dbo].[employeeswipedclose123]    Script Date: 12/11/2012 12:04:34 ******/
CREATE TYPE [dbo].[employeeswipedclose123] AS TABLE(
    [empid] [int] NULL,
    [datetoday] [datetime] NULL,
    [Swipepk] [int] NULL
)
GO
  CREATE PROCEDURE dbo.CloseAttendance (@closingemployee dbo.employeeswipedclose123 READONLY )
AS
BEGIN

   MERGE EmployeSwipeDaily_tbl AS Target

   USING @closingemployee AS Source

   ON (Target.empid = Source.empid) and (Target.Date = Source.datetoday)

   WHEN MATCHED THEN 
       BEGIN 
           UPDATE    Target
            SET Target. IsCompleted = N'Y'
             WHERE     (Source.swipePK = Target.Swipepk) AND (Source.empid = Target.empid) AND (Target.Date = Source.datetoday)   

         WHEN NOT MATCHED THEN

       INSERT INTO Target
       (empid, Swipin, SwipeOut, Date, Duration, deviceid, InStatus, Outstatus, Invalue, OutValue, IsCompleted, CompletedDate)
        VALUES     (@empid, CONVERT(DATETIME, ' 00:00:00', 102), CONVERT(DATETIME, ' 00:00:00', 102),@datetoday, CONVERT(DATETIME, 
                      ' 00:00:00', 102), 0, N'A', N'A', 0, 0, N'Y',(select GETDATE()) )

END


GO

但现在我想要的是在存储过程中我想循环Datatable并检查一个条件

比如这样

for(int i=0 ;i<dt.count;i++)
{
   if(dt.rows[i][swipepk]==0)
   {
       insert into employe swipe tbl()
   }
   else 
   {
       update employee tbl
   }
}

任何人都可以建议一个更好的解决方案来循环存储过程中的数据表？

Answer 1

由于您使用的是SQL Server 2008,因此这正是使用该MERGE语句的方案!没有循环或任何需要的东西 - 只需一个MERGE语句即可!

CREATE PROCEDURE dbo.CloseAttendance (@closingemployee dbo.Employeedata READONLY)
BEGIN
   -- this is the target of your MERGE - where the data is supposed to go
   MERGE dbo.Employees AS Target
   -- this is the source where the data to be merged comes from
   USING @closingemployee AS Source
   -- set up a "join" condition for those two sets of data
   ON Target.empid = Source.empid
   -- now define what to do when that JOIN condition matches
   WHEN MATCHED THEN 
       UPDATE 
          SET Target.SomeColumn = Source.Swipepk  --- or WHATEVER you need to update here!
   -- now define what to do when that JOIN condition DOES NOT match (e.g. new employee)
   WHEN NOT MATCHED THEN
      INSERT(EmpId, CategoryName, Swipepk)
      VALUES(Source.EmpId, Source.CategoryName, Source.Swipepk) ;
END

当然,您也可以做其他事情 - 如果需要,您可以定义更多匹配/不匹配的标准.

这个MERGE语句运行一次,并不会在单程所有的工作-没有循环,没有RBAR(行到痛苦的排)处理-没有什么之类的.一个不错的,快速的,基于集合的声明,你已经完成了!

更新:根据您更新的问题,我发现您的声明中有三个主要错误MERGE:

 WHEN MATCHED THEN 
    BEGIN                                 <=== ERROR #1 : you CANNOT have a BEGIN here!
        UPDATE Target
        SET Target.IsCompleted = N'Y'
        WHERE (Source.swipePK = Target.Swipepk)  <=== ERROR #2 : you CANNOT have 
          AND (Source.empid = Target.empid)                      additional WHERE 
          AND (Target.Date = Source.datetoday)                   clause on the UPDATE

WHEN NOT MATCHED THEN
   INSERT INTO Target              <=== ERROR #3: you CANNOT define a INSERT INTO ....
                                      the "INTO" table is already a given by the MERGE
   (empid, Swipin, SwipeOut, Date, Duration, deviceid, InStatus, Outstatus, Invalue, OutValue, IsCompleted, CompletedDate)
    VALUES     (@empid, CONVERT(DATETIME, ' 00:00:00', 102), CONVERT(DATETIME, ' 00:00:00', 102),@datetoday, CONVERT(DATETIME, 
                  ' 00:00:00', 102), 0, N'A', N'A', 0, 0, N'Y',(select GETDATE()) )