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From Bryan Pendleton <bpendleton.de...@gmail.com>
Subject Re: Cannot read table while writing transaction in another connection
Date Tue, 31 Jul 2012 00:27:01 GMT
> I would have expected that around line 175 I would get the row count
> as it was before the uncommitted
> transaction started and that no lock would be needed to just read.

Unfortunately, Derby doesn't currently implement these "snapshot isolation"
types of semantics.

> Is this the way it is supposed to work? If so, is there some
> configuration parameters that I can set up
> to get the behavior I expected?

You can try using a lower isolation level:
http://db.apache.org/derby/docs/10.9/devguide/cdevconcepts15366.html

But that's not exactly the same thing (e.g., at a lower isolation level,
it might be that the count returns the instantaneous count of rows
in the table, including some rows from uncommitted transactions).

thanks,

bryan



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