Re: Refactoring psql for backward-compatibility - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: Refactoring psql for backward-compatibility
Date
Msg-id 20051214140649.GB9278@surnet.cl
Whole thread Raw
In response to Re: Refactoring psql for backward-compatibility  (Andrew Dunstan <andrew@dunslane.net>)
List pgsql-hackers
Andrew Dunstan wrote:
> 
> David Fetter wrote:
> 
> >I'd much appeciate tips, specific RTFMs and feedback on this so I can
> >get cracking on a patch.
> 
> well, before you even start on a patch we should have agreement that 
> this is a good idea, and an agreed design.
> 
> This is really an m * n problem. That's what does indeed make it a 
> maintenance nightmare. A new version of psql implements a new command 
> and suddenly we have to provide compatibility versions (if possible) for 
> m server versions back. Repeat for n versions of psql.

You just need to give the user a message saying "this server version
does not implement this command".

Of course, the design needs to support the fact that some server
versions will not implement all backslash commands.  This should not be
too difficult.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.


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