I have a large script file (nearly 300MB, and feasibly bigger in the future) that I am trying to run. It has been suggested in the comments of Gulzar\'s answer to my questi
sqlcmd -t {n}
Where {n} must be a number between 0 and 65535.
Note that your question is a bit misleading since the server has no concept of a timeout and therefore you cannot set the timeout within your script.
In your context the timeout is enforced by sqlcmd