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From "Curry, David CIV NAVAIR 41K300D" <david.l.cu...@navy.mil>
Subject Seg file not updating?
Date Thu, 07 Aug 2008 17:47:30 GMT
Vista, NetBeans 6.0, using embedded Derby driver.

I have 2 apps that share a database.  admin.jar is the admin app,
demo.jar is a simple client that cannot change data in the database.
Both apps are in the same folder, along with the database folder.

When I make data changes to the db using admin, and close admin and run
demo, I can see the data changes, no problem.

But when I look at seg\files, none of them have had their
modified/accessed timestamps updated.  The log file does have the
timestamp updated.  When I examine the seg\file that I know should have
the new data, it does not, but the log file does have the new data.  

Now, I have made data changes and seen the seg\file updated - that's how
I knew which seg\file was storing that particular piece of data - and no
other seg\files change when I change that data, so I'm quite confident
about this.  The weird part is that sometimes the seg\file WILL update
several minutes after closing admin - just POOF, it changes, timestamp
and all.

I read that sometimes the JVM hangs around and keeps the derby driver
alive, so the buffers aren't getting flushed.  I added a windowClose
handler, and I call System.gc() to force garbage collection, but that's
specious at best, and doesn't seem to have any effect.

I'm concerned that I, when I close admin, I am leaving changes pending
in the log file, not yet committed to the seg\file.  This might be a
problem if I want to copy the database folder back to the netbeans derby
folder so that I can add a field.  Will I lose the data changes I made
using admin?

Has anyone else seen this type of behavior?  Is it a problem?


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