db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Knut Anders Hatlen <knut.hat...@oracle.com>
Subject Re: Suitable test query for Derby?
Date Fri, 13 Apr 2012 19:29:20 GMT
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

Knut Anders

View raw message