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From Mehran Sowdaey <Mehran.Sowd...@Sun.COM>
Subject Re: table locking
Date Tue, 22 Nov 2005 20:01:00 GMT
Please see:

<http://db.apache.org/derby/docs/10.0/manuals/develop/develop63.html>

(Table 2). This is a 10.0 document but we have seen the same in 10.1

thanks,
-------
mehran

Mike Matrigali wrote On 11/22/05 11:24,:
> Derby uses row locking by default, can you please explain why you
> think it is table locking.  Derby does get table level intent locks,
> to enable the row locking feature - so for instances when updating
> a row in a table you will get a table level IX and a row level X, but
> another transaction will also be able to get a table level IX and a
> row level X lock on another row.
> 
> There are situations depending on isolation level and lock escalation
> where real table level locks are requested, not sure if you are running
> into that.  More information is needed.
> 
> Mehran Sowdaey wrote:
> 
>>Hi,
>>
>>When running derby in server mode if autocommit is turned off table
>>locking occurs. Is there anyway to prevent that and have row level
>>locking. We have tried changing a few of derby parameters without success.
>>
>>thanks,
>>-------
>>mehran
>>
>>
>>
> 
> 

-- 
Mehran Sowdaey
Sun Microsystems, Inc. Mailstop UBRM06-304
500 Eldorado Blvd. Broomfield, CO. 80021
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Phone: 303-272-3192


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