pixeloution

-- the #1 likely use-case for this is when using a mySQL table as queue, which is something
-- that should be avoided anyway ... but this allows you to mark items as "in process" 
-- and return the ids of the items, without using a table lock (mySQL)

-- sets up the variable
SET @IDS := null;

-- should update all the rows and return a list of updated ids in @IDS. Assume:
-- status 1 means "to be processed"
-- status 2 means "being processed"