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From Dyre.Tjeldv...@Sun.COM
Subject Re: Cache session data in the client driver?
Date Mon, 22 Oct 2007 12:57:22 GMT
Dag.Wanvik@Sun.COM (Dag H. Wanvik) writes:

> Dyre.Tjeldvoll@Sun.COM writes:
>
>> For the second option I was wondering if it would be possible to use
>> the EXCSQLSET trick that √ėyvind used for setQueryTimeout, in
>> reverse. According to the DRDA spec (v4, volume 3, page 359-360) it is
>> possible to add one or more SQLSTT objects after SQLCARD in the reply,
>> but as far as I can tell, there doesn't seem to be any methods for
>> doing so on the server, nor do I see any methods for extracting the
>> values when parsing the reply on the client. But they would not be too
>> difficult to add, I think.
>>
>> If this method can be made to work I think it would be possible to
>> cache additional session information when this becomes relevant.  It
>> would also be possible to use EXCSQLSET to batch session state changes
>> going from the client to the server.
>
> I read the standard the same way; the RTNSETSTT docs is pretty clear:
>
> "Return SET statement (RTNSETSTT) controls whether the target server
> must return one or more SQLSTT reply data objects, each containing an
> SQL SET statement for a special register whose setting has been
> modified on the current connection, upon successful processing of the
> command, if any special register has had its setting modified during
> execution of the command."
>
> I guess "special register whose setting has been modified on the
> current connection" would cover session state variables.

Thanks Dag. It is always nice when someone confirms your
interpretation of the DRDA spec (or any other spec for that
matter) :)

-- 
dt


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