Re: Dump pageinspect to 1.2: page_header with pg_lsn datatype

Andres Freund escribió:
> On 2014-02-24 17:53:31 +0900, Michael Paquier wrote:
> > On Sun, Feb 23, 2014 at 6:09 AM, Alvaro Herrera <alvherre@2ndquadrant.com>wrote:
> > 
> > > Michael Paquier escribió:
> > > > Hi all,
> > > >
> > > > Please find attached a patch to dump pageinspect to 1.2. This
> > > > simply changes page_header to use the new internal datatype
> > > > pg_lsn instead of text.
> > >
> > > Uhm.  Does this crash if you pg_upgrade a server that has 1.1
> > > installed?
> > >
> > Oops yes you're right., it is obviously broken. Just re-thinking
> > about that, dumping this module just to change an argument type does
> > not seem to be worth the code complication. Thoughts?
> 
> It seem simple to support both, old and new type. page_header() (which
> IIRC is the only thing returning an LSN) likely uses
> get_call_result_type(). So you can just check what it's
> expecting. Either support both types or error out if it's the old
> extension version.

Yeah, erroring out seems good enough.  Particularly if you add a hint
saying "please upgrade the extension".

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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