The most common error I see in badly scalable database code is reckless use
of the connection object. For all multi-user database programming (which
accounts for most of the work these days), database connections are a limited
resource. Don't let it be your code that is hanging on to his connection way
after you are finished with it. I am *not* saying that all work can be done
disconnected. I am simply asking you to keep in mind that Connections are
precious things. Try to do these two things:
- Open Connections as Late as possible.
- Close Connections as Early as possible.
Most people concentrate on closing their connections early. This is good and
well known. But I have seen more than my share of code (including mine!) that
opened database connections too early.