Using MySQL and Hibernate, what would be the preferred way to update a column to NOW(), so that I get the time on the database server, not the application server? Do I have to write my own SQL update statement, or is there another way to have Hibernate pass NOW() along as the value to use?

Thanks,
Lee Grey

I guess a little more detail couldn't hurt.

I'm trying to mark an open session as closed by putting the current timestamp into the "closed" column. I don't think there's anything that I can put into the UserSession object's closed property that would cause the database to put the value from NOW() into it.

What other alternatives do I have?

Thanks,
Lee

(1) use new Date()
(2) use direct JDBC or a custom persister

Along the lines of a customer persister approach, you could define a utility class that periodically queries the actual database for the current timestamp.

If you are willing to sacrifice some accuracy for performance, you can set this class up so that it only periodically queries the database and stores a "drift" value from the current system clock. (You lose the nanosecond precision of database timestamps because System.currentTimeMillis() doesn't support nanoseconds, plus you lose the accuracy of your own system clocks drift in between polling intervals.)

Some sample SQL to query the current timestamp for DB2 would be:

SELECT CURRENT TIMESTAMP FROM SYSIBM.SYSDUMMY

I'm not sure offhand what the SQL for MySQL would be, but it should be similar (you might need to setup a "dummy" table with a single row to make this work).