Re: Old-client/new-server...issues?

On 7/06/2011 8:32 AM, Steve Crawford wrote:
> I am working on my final 7.4 -> 9.0 upgrade. Data-type (auto-coalesce
> and foreign-key), query and encoding issues are resolved. Dump/restore
> is tested. But...
>
> I have a few old client systems that are difficult/infeasible to update.
> I know the recommended procedure is to update clients ahead of server
> but what problems am I likely to encounter connecting to a 9.0 server
> from a 7.4 client?

Reliance on implicit casts to/from text in queries may be a problem.

You could also have issues if the clients rely on metadata obtained from
the database - for example, enumerating columns in a table or listing
tables. I know this has been an issue when using older JDBC drivers
against newer servers, and wouldn't be too surprised if similar issues
existed with libpq.

--
Craig Ringer

Tech-related writing at http://soapyfrogs.blogspot.com/