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From Rick Hillegas <Richard.Hille...@Sun.COM>
Subject Re: cancel a running query?
Date Fri, 10 Oct 2008 13:01:57 GMT
Hi Dirk,

Yes, Derby does support Statement.setQueryTimeout(), at least as 
verified by the Derby regression test 
org.apache.derbyTesting.functionTests.tests.lang.SetQueryTimeoutTest. 
That's a good defense if you suspect in advance that your queries may 
ramble on. It leaves the lingering issue of how to cancel a runaway 
query that you (or someone else) didn't limit before the query started.

Hope this helps,
-Rick

Dirk Flachbart wrote:
>
> Doesn't Derby support Statement.setQueryTimeout() ?
>
>
> Dirk
>
>
> derby@segel.com <mailto:derby@segel.com> wrote:
>> A rollback doesn't "cancel" a query. Meaning that you can't stop the query
>> until it completes.
>>
>> The rollback will reverse the results of a transaction after the SQL
>> statement completes. A query is unaffected because its not a SQL statement
>> that changes the database. (query == SELECT, other statements UPDATE,DELETE,
>> INSERT, etc ... do change the data.)
>>
>> So if you start  a query, there isn't a way to have some sort of query
>> timeout or call to prematurely end the query. (Perhaps you need to consider
>> threading your app...)
>>
>> HTH
>>
>> -Mike
>>
>>
>>   
>>> -----Original Message-----
>>> From: Dag.Wanvik@Sun.COM <mailto:Dag.Wanvik@Sun.COM> [mailto:Dag.Wanvik@Sun.COM]
>>> Sent: Thursday, October 09, 2008 9:09 PM
>>> To: Derby Discussion
>>> Subject: Re: cancel a running query?
>>>
>>> Rick Hillegas <Richard.Hillegas@Sun.COM> <mailto:Richard.Hillegas@Sun.COM>
writes:
>>>
>>>     
>>>>  conn.rollback();
>>>>       
>>> Doesn't the rollback block on synchronizion on the connection?
>>>
>>> Dag
>>>     
>>
>>   
>


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