Re: Implementing RESET CONNECTION ... - Mailing list pgsql-patches

From Oliver Jowett
Subject Re: Implementing RESET CONNECTION ...
Date
Msg-id 41D9EF6C.4000502@opencloud.com
Whole thread Raw
In response to Re: Implementing RESET CONNECTION ...  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Implementing RESET CONNECTION ...  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-patches
Tom Lane wrote:
> Kris Jurka <books@ejurka.com> writes:
>
>>Also I don't like the idea of cleaning up prepared statements.
>
>
> Hmm.  This seems a bit eye-of-the-beholder-ish, ie you could make a
> legitimate argument either way.  Maybe the RESET CONNECTION command
> should have an option whether to zap prepared statements or not?

That doesn't really help the JDBC driver case. The problem is that there
are prepared statements that have been set up by the driver invisibly to
the user. Zapping them will make the driver break, and it's too easy for
the user code to do a full RESET CONNECTION and accidently zap them.

Yes, you can break the JDBC driver currently by doing explicit
DEALLOCATEs of its prepared statements -- but you have to do that quite
deliberately so it's less of a problem.

Having notification of either prepared statement deallocation or
connection reset (a la ParameterStatus for GUC changes) would help the
driver to recover from this case.

-O

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