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From Dag.Wan...@Sun.COM (Dag H. Wanvik)
Subject Re: Cache session data in the client driver?
Date Thu, 18 Oct 2007 14:49:26 GMT
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.



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