mySQL Timer for locked row
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I am not very expereienced with advanced mySQL but I was wonder what is the best way to implement a time out. I have an iPhone app that 'locks' a row in a table while it is creating the content to be written back to it. It's just a BOOL column that I toggle back and forth. The problem is, if my app crashes or they lose network connection while its locked it will not unlock. I would like to set a 5min timer or something on the server to unlock the row if they fail to complete the process within that time. My web api is written in PHP.

Can I do this with mySQL? Do I need to create a cron job?