How to LOCK a row in MySQL?

I'm working on a CRM desktop application which is going to be used by more than one agent at a time, and all agents will go thro开发者_运维知识库ugh the same list of customers. What I need to do here is to avoid conflicts between agents, so once an agent selects a customer from the list, others shouldn't be able to see that row anymore, or in another words they shouldn't be able to select that customer row until the first agent is done ! The simplest way that comes in mind wich may sound stupid is to add two fields LOCK(BIT), LOCK_EXPIRY(DATETIME) and manage that. I don't know But I think there should be another way to lock a row for particular session. I searched on Google and I found two InnoDB locking methods but I'm not sure if those can help me here in this case.

I suggest you add the two fields you described, except replace LOCK(BIT) with LOCKED_BY(AGENT_ID). Otherwise if the agent that has locked the list of customers refreshes his/her page, the locked rows may disappear until the lock expires.

I think you can use GET_LOCK() function with MySQL:

http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_get-lock