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From Dag.Wan...@Sun.COM (Dag H. Wanvik)
Subject Re: Can someone explain this deadlock?
Date Sun, 06 Sep 2009 01:36:11 GMT
T K <sanokistoka@yahoo.com> writes:

> Does Derby support SQL hints, so I can tell it to NOLOCK on the SELECT?

You can try to lower the isolation level for the select to read
uncommitted,
cf. http://db.apache.org/derby/docs/10.5/ref/rrefsqlj41360.html using
the "WITH UR",
if this is ok with your application logic.

According to http://db.apache.org/derby/papers/btree_package.html,
no locks are acquired in this case.

But I am not sure that would prevent a momentary read lock being
requested while the row is being read, does anyone know for sure?

Dag

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