SQL 中多行转为一行

Create table Emp_Announcement_Account
(
AnnouncementID Int not Null,
AccountNum Int Not Null,
SubAccount Int Not Null
)
Alter Table Emp_Announcement_Account
Add Constraint PK_Emp_Announcement_Account PRIMARY KEY(AnnouncementID,AccountNum,SubAccount)

insert into Emp_Announcement_Account values(123,789,0)
insert into Emp_Announcement_Account values(123,789,1)
insert into Emp_Announcement_Account values(123,12313,2)


Create Function UDF_SIS30_BO_RMSAnnouncement_MergSpecifiedMembers
(
@AnnouncementID Int
) Returns Varchar(8000)
As
Begin
Declare @temp Varchar(1000)
Set @temp='' --设置为空,如果不设置则返回 NULL

--连接成一行
Select @temp=@temp+','+cast(AccountNum   as   varchar)+'-'+Cast(SubAccount as varchar)
From Emp_Announcement_Account Where AnnouncementID=@AnnouncementID
--去掉第一个','
If len(@temp)>0
    Set @temp=Right(@temp,len(@temp)-1)
Return @temp
End