SQL Server OUTPUT clause - sql-server

Question

I am a little stuck with why I can not seem to get the 'new identity' of the inserted row with the statement below. SCOPE_IDENTITY() just returns null.
declare #WorkRequestQueueID int
declare #LastException nvarchar(MAX)
set #WorkRequestQueueID = 1
set #LastException = 'test'
set nocount off
DELETE dbo.WorkRequestQueue
OUTPUT
DELETED.MessageEnvelope,
DELETED.Attempts,
#LastException,
GetUtcdate(), -- WorkItemPoisened datetime
DELETED.WorkItemReceived_UTC
INTO dbo.FaildMessages
FROM dbo.WorkRequestQueue
WHERE
WorkRequestQueue.ID = #WorkRequestQueueID
IF ##ROWCOUNT = 0
RAISERROR ('Record not found', 16, 1)
SELECT Cast(SCOPE_IDENTITY() as int)
Any assistance would be most appreciated.
For now I use a workaround this like so.
declare #WorkRequestQueueID int
declare #LastException nvarchar(MAX)
set #WorkRequestQueueID = 7
set #LastException = 'test'
set nocount on
set xact_abort on
DECLARE #Failed TABLE
(
MessageEnvelope xml,
Attempts smallint,
LastException nvarchar(max),
WorkItemPoisened_UTC datetime,
WorkItemReceived_UTC datetime
)
BEGIN TRAN
DELETE dbo.WorkRequestQueue
OUTPUT
DELETED.MessageEnvelope,
DELETED.Attempts,
#LastException,
GetUtcdate(), -- WorkItemPoisened datetime
DELETED.WorkItemReceived_UTC
INTO
#Failed
FROM
dbo.WorkRequestQueue
WHERE
WorkRequestQueue.ID = #WorkRequestQueueID
IF ##ROWCOUNT = 0 BEGIN
RAISERROR ('Record not found', 16, 1)
Rollback
END ELSE BEGIN
insert into dbo.FaildMessages select * from #Failed
COMMIT TRAN
SELECT Cast(SCOPE_IDENTITY() as int)
END

Answer 1

EDITED FEB'2013
#MartinSmith alerts us that this bug don't want be fixed by Microsoft.
"Posted by Microsoft on 2/27/2013 at 2:18 PM Hello Martin, We
investigated the issue and found that changing the behavior is not an
easy thing to do. It would basically require redefining some of the
behavior when both INSERT & OUTPUT INTO target has identity columns.
Given the nature of the problem & the uncommon scenario, we have
decided not to fix the issue. -- Umachandar, SQL Programmability
Team"
EDITED OCT'2012
This is caused by a bug:
Testing bug:
Quoting OUTPUT Clause doc:
##IDENTITY, SCOPE_IDENTITY, and IDENT_CURRENT return identity values
generated only by the nested DML statement, and not those generated by
the outer INSERT statement.
After test it It seems that scope_identity() only works if outer operation is an insert in a table with identity columns:
Test 1: Delete
create table #t ( a char(1) );
create table #d ( a char(1), i int identity );
insert into #t
values ('a'),('b'),('c');
delete #t
output deleted.a into #d;
select SCOPE_IDENTITY(), * from #d;
a i
---- - -
null a 1
null b 2
null c 3
Test 2: Inserting in outer table with identity
create table #t ( a char(1), i int identity );
create table #d ( a char(1), i int identity );
insert into #t
values ('x'),('x'),('x');
insert into #t
output inserted.a into #d
values ('a'),('b');
select scope_identity(), * from #d;
a i
- - -
2 a 1
2 b 2
Test 3: Inserting in outer table without identity
create table #t ( a char(1) );
create table #d ( a char(1), i int identity );
insert into #t
values ('x'),('x'),('x');
insert into #t
output inserted.a into #d
values ('a'),('b');
select scope_identity(), * from #d;
a i
---- - -
null a 1
null b 2

Answer 2

You might try to use a table variable for your output clause, thus allowing you to explicitly insert into FaildMessages:
declare #WorkRequestQueueID int
declare #LastException nvarchar(MAX)
set #WorkRequestQueueID = 1
set #LastException = 'test'
set nocount off
-- Declare a table variable to capture output
DECLARE #output TABLE (
MessageEnvelope VARCHAR(50), -- Guessing at datatypes
Attempts INT, -- Guessing at datatypes
WorkItemReceived_UTC DATETIME -- Guessing at datatypes
)
-- Run the deletion with output
DELETE dbo.WorkRequestQueue
OUTPUT
DELETED.MessageEnvelope,
DELETED.Attempts,
DELETED.WorkItemReceived_UTC
-- Use the table var
INTO #output
FROM dbo.WorkRequestQueue
WHERE
WorkRequestQueue.ID = #WorkRequestQueueID
-- Explicitly insert
INSERT
INTO dbo.FaildMessages
SELECT
MessageEnvelope,
Attempts,
#LastException,
GetUtcdate(), -- WorkItemPoisened datetime
WorkItemReceived_UTC
FROM #output
IF ##ROWCOUNT = 0
RAISERROR ('Record not found', 16, 1)
SELECT Cast(SCOPE_IDENTITY() as int)