Re: Dump pageinspect to 1.2: page_header with pg_lsn datatype

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.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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