Can I Select and Update at the same time?

Question

This is an over-simplified explanation of what I'm working on.
I have a table with status column. Multiple instances of the application will pull the contents of the first row with a status of NEW, update the status to WORKING and then go to work on the contents.
It's easy enough to do this with two database calls; first the SELECT then the UPDATE. But I want to do it all in one call so that another instance of the application doesn't pull the same row. Sort of like a SELECT_AND_UPDATE thing.

Is a stored procedure the best way to go?

Answer 1

You could use the OUTPUT statement.

DECLARE @Table TABLE (ID INTEGER, Status VARCHAR(32))
INSERT INTO @Table VALUES (1, 'New')
INSERT INTO @Table VALUES (2, 'New')
INSERT INTO @Table VALUES (3, 'Working')

UPDATE  @Table
SET     Status = 'Working'
OUTPUT  Inserted.*
FROM    @Table t1
        INNER JOIN (
          SELECT  TOP 1 ID 
          FROM    @Table
          WHERE   Status = 'New'
        ) t2 ON t2.ID = t1.ID