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From Brett Wooldridge <brett.wooldri...@gmail.com>
Subject Re: Suitable test query for Derby?
Date Sun, 15 Apr 2012 23:33:06 GMT
Well, full disclosure, I'm a contributor to Bitronix. :-)

Brett

Sent from my iPhone

On Apr 15, 2012, at 20:52, Martin Lichtin <lichtin@yahoo.com> wrote:

> Thanks Brett and Knut.
> Interesting you guys mention Bitronix TM.
> I was dealing with Atomikos when this question of a test query came up.
> Unlike Bitronix it doesn't support the JDBC4 isValid().
>
> -------- Original Message --------
> Subject: Re: Suitable test query for Derby?
> From: Knut Anders Hatlen <knut.hatlen@oracle.com>
> To: Derby Discussion <derby-user@db.apache.org>
> Date: 4/13/2012 9:29 PM
>
>> Martin Lichtin<lichtin@yahoo.com>  writes:
>>
>>> Hi
>>> Implementations of connection pooling typically use a "test query" to first check
>>> whether a connection is still valid before sending the actual query across.
>>> A test query looks like
>>>   SELECT SYSDATE FROM DUAL (eg. PostgreSQL or Oracle)
>>> or
>>>   SELECT 1 (eg. Ingres)
>>>
>>> What is a suitable test query for Derby? I couldn't find one off-hand.
>>
>> VALUES 1 would be Derby's equivalent of the Ingres query. Or you could
>> use isValid(), as Brett suggested. (If I remember correctly, the client
>> driver actually implements isValid() by executing VALUES 1 on the
>> server.)
>>

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