T-SQL Output Clause: How to access the old Identity ID

Question

Hi There,

I have a T-SQL statement that basically does an insert and OUTPUTs some of the inserted values to a table variable for later processing.

Is there a way for me to store the old Identity ID of the selected records into my table variable. If I use the code below, I get "The multi-part identifier "a.ID" could not be bound." error.

DECLARE @act_map_matrix table(new_act_id INT, old_ID int)
DECLARE @new_script_id int
SET @new_script_id = 1

INSERT INTO Act
(ScriptID, Number, SubNumber, SortOrder, Title, IsDeleted)
OUTPUT inserted.ID, a.ID INTO @act_map_matrix
 SELECT 
  @new_scriptID, a.Number, a.SubNumber, a.SortOrder, a.Title, a.IsDeleted
 FROM Act a WHERE a.ScriptID = 2

Thanks!

Answer 1

You'll have to join back @act_map_matrix onto Act to get the "old" value.

It's simply not available in the INSERT statement

edit: one hopes that @new_scriptID and "scriptid=2" could be the join column

Answer 2

I was having your same problem and found a solution at http://sqlblog.com/blogs/adam_machanic/archive/2009/08/24/dr-output-or-how-i-learned-to-stop-worrying-and-love-the-merge.aspx

Basically it hacks the MERGE command to use that for insert so you can access a source field in the OUTPUT clause that wasn't inserted.

MERGE INTO people AS tgt
USING #data AS src ON
    1=0 --Never match
WHEN NOT MATCHED THEN
    INSERT
    (
        name,
        current_salary
    )
    VALUES
    (
        src.name,
        src.salary
    )
OUTPUT
    src.input_surrogate,
    inserted.person_id
INTO #surrogate_map;