Multiple OUTPUT clauses in MERGE/INSERT/DELETE SQL commands?

Question

I have a T-SQL script that implements some synchronization logic using OUTPUT clause in MERGEs and INSERTs.

Now I

Answer 1

Martin Smith is right, it is not possible to have two OUTPUT INTO clauses in one MERGE statement, but he is also right that it is possible to have one OUTPUT INTO and one OUTPUT clause. OUTPUT INTO inserts its result set directly into the given table and the simple OUTPUT returns result set to the caller.

So, you can wrap the MERGE statement into a stored procedure and then use INSERT ... EXEC to insert result set of the simple OUTPUT into a second table.

CREATE PROCEDURE [dbo].[TestMerge]
AS
BEGIN
    SET NOCOUNT ON;
    SET XACT_ABORT ON;

    MERGE TABLE_TARGET AS T
    USING TABLE_SOURCE AS S
    ON (T.Code = S.Code) 
    WHEN MATCHED AND T.IsDeleted = 0x0
        THEN UPDATE SET ....
    WHEN NOT MATCHED BY TARGET 
        THEN INSERT ....
    OUTPUT inserted.SqlId, inserted.IncId
    INTO sync_table
    OUTPUT $action AS MergeAction, inserted.Name, inserted.Code;
END

Usage

INSERT INTO report_table
EXEC [dbo].[TestMerge];

This will insert rows into sync_table and into report_table.

If you examine execution plan you'll see that INSERT ... EXEC creates a temporary table behind the scenes (see also The Hidden Costs of INSERT EXEC by Adam Machanic).