问题
In SQL Server 2005 I am inserting a row into a table using a stored procedure and I want to fetch the new primary key value just after inserting that row. I am using following approach to get primary key value after insertion row
Create Proc Sp_Test
@testEmail varchar(20)=null,-- Should be Unique
@testName varchar(20)=null -- Should be Unique
as
begin
insert into tableTest (testUserEmail,testUserName)values (@testValue,@testName)
select MAX(ID) from tableTest --ID is Primary Key
--or
select ID from tableTest where testUserEmail =@testValue and testUserName = @testName
--or
select SCOPE_IDENTITY() as ID
end
Please suggest me which approach is better to perform described task.
回答1:
By all means - use the SCOPE_IDENTITY() if your ID column is an INT IDENTITY - only that will give you the correct results!
The first approach with the MAX(ID) will fail terribly if you have multiple clients inserting rows almost at the same time - you'll get false results back. Don't use that!
The third approach might fail if another entry with the same values for E-Mail and name already exists.
Also, as a side-note: you should never use sp_ as your prefix! This is a Microsoft-reserved prefix and has downsides in terms of performance - use something else.
回答2:
If you have an Identity column as primary key you should use SCOPE_IDENTITY()
You could also use the OUTPUT Clause to return the ID.
insert into tableTest(testUserEmail,testUserName)
output inserted.ID
values (@testValue, @testName)
来源：https://stackoverflow.com/questions/6799738/primary-key-value-after-insertion-of-row-in-sql-server-2005