----- Original Message ----- From: "PhilCope" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, June 16, 2008 3:58 PM
Subject: Thread Interruption in large Database



I have a large cloudscape 5 database (over 5million records) and I have found
that when a ResultsSet includes all or many of these records, the initial
call to ResultsSet.next() takes a very long (but finite) time (I would
estimate about 10-15mins) . I can (indeed have) arrange the code so that
this call occurs in a separate java thread which can be interrupted from the UI thread. BUT, as you may know, java threads that are set to as interrupted
continue to execute until either application code or some "system" calls
actually check the interrupted state of the running thread.

So, given this background info, my questions on Derby are

1. Have any significant performance improvements been made such that, for
databases of this size, migrating from cloudscape to Derby would provide a
significantly better response time ?

2. If not, are there any improvements to the responsiveness of the
timeconsuming call to .next() to the setting of the interrupted flag on the
current thread in Derby ?

Thanks

Phil Cope

Phil, it actaully sounds like a design issue... are the fields are indexed and do you have to bring back all 5 mil records and a step through them... why not 10 at a time or something. I think any dB (machine mem, heap whatever) will start to take strain with a 5 million recordset. Whats going to happen when the dB has 50 million records? The design should not depend on it. ie if the search fields are indexed and you bring back 50 at a time, it should be pretty quick. Sooner or later you going to get out of mem errors from Java... sounds like it anyway.

Good luck ;)

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