Re: Make relfile tombstone files conditional on WAL level - Mailing list pgsql-hackers

From Dilip Kumar
Subject Re: Make relfile tombstone files conditional on WAL level
Date
Msg-id CAFiTN-u6rsQEPMn8Utv9tjbHgOT0r=7fyk41TqPTcxcPp8_N1g@mail.gmail.com
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In response to Re: Make relfile tombstone files conditional on WAL level  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: Make relfile tombstone files conditional on WAL level
List pgsql-hackers
On Thu, Jan 6, 2022 at 7:22 PM Robert Haas <robertmhaas@gmail.com> wrote:
On Thu, Jan 6, 2022 at 3:47 AM Thomas Munro <thomas.munro@gmail.com> wrote:
> Another problem is that relfilenodes are normally allocated with
> GetNewOidWithIndex(), and initially match a relation's OID.  We'd need
> a new allocator, and they won't be able to match the OID in general
> (while we have 32 bit OIDs at least).

Personally I'm not sad about that. Values that are the same in simple
cases but diverge in more complex cases are kind of a trap for the
unwary. There's no real reason to have them ever match. Yeah, in
theory, it makes it easier to tell which file matches which relation,
but in practice, you always have to double-check in case the table has
ever been rewritten. It doesn't seem worth continuing to contort the
code for a property we can't guarantee anyway.

Make sense, I have started working on this idea, I will try to post the first version by early next week.

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com

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