Best practice updating data in webapps?

Maybe a bit outside the scope of PGSQL but when designing webapps where different users
can edit the same record at the same time, what is the best way to solve this situation?
One way is to use an update field, that gets selected with rest of the data and when
updating the data, check this update field with the one in the db; if they don't match,
someone else has updated the record before you..
But is this the best way?

Regards,

BTJ

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Bjørn T Johansen

btj(at)havleik(dot)no
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Someone wrote:
"I understand that if you play a Windows CD backwards you hear strange Satanic messages"
To which someone replied:
"It's even worse than that; play it forwards and it installs Windows"
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