Re: pgsql: pageinspect: Fix types used for bt_metap() columns.

On 2020-Mar-08, Peter Geoghegan wrote:

> Fix these issues by changing the declaration of bt_metap() to
> consistently use data types that can reliably represent all possible
> values. This fixes things on HEAD only. No backpatch, since it doesn't
> seem like there is a safe way to fix the issue without including a new
> version of the pageinspect extension (HEAD/Postgres 13 already
> introduced a new version of the extension). Besides, the oldest_xact
> issue has been around since the release of Postgres 11, and we haven't
> heard any complaints about it before now.

This may be a good time to think through about how to implement a
version history for an extension that enables users to go from pg12's
current 1.7 pageinspect to a new fixed version in pg12, say 1.7.1, and
in HEAD provide an upgrade path from both 1.7 and 1.7.1 to master's 1.8.
Then you can pg_upgrade from pg12 to pg13 having either 1.7 or 1.7.1,
and you will be able to get to 1.8 nonetheless.

Does that make sense?

The current problem might not be serious enough to warrant actually
writing the code that would be needed, but I propose to at least think
about it.

--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services