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From: Masahiko Sawada <sawada.mshk@gmail.com>
Date: Wed, 11 Mar 2026 14:48:08 -0700
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 <CAD21AoBdgM+4X=Wg0T==C9ahenm2nUb=q5AxxeEb_JVoKOzbgw@mail.gmail.com>
Subject: Re: tid_blockno() and tid_offset() accessor functions
To: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Cc: pgsql-hackers@postgresql.org
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On Fri, Feb 27, 2026 at 10:59=E2=80=AFAM Ayush Tiwari
<ayushtiwari.slg01@gmail.com> wrote:
>
> Hi hackers,
>
> As of now we don't have any built-in way to extract the block and offset =
components from a TID. When people need to group by page (like for bloat an=
alysis) or filter by specific blocks, they usually end up using the `ctid::=
text::point` hack:
>
>     SELECT (ctid::text::point)[0]::bigint AS blockno,
>            (ctid::text::point)[1]::int    AS offset
>     FROM my_table;
>
> This works, but it's pretty clunky, relies on the text representation, an=
d isn't great if you're trying to parse TIDs outside of SQL.
>
> The attached patch adds two simple accessor functions:
> - `tid_blockno(tid) -> bigint`
> - `tid_offset(tid) -> integer`

How about adding the subscripting support for tid data type? For
example, ctid[0] returns bigint and ctid[1] returns int.

Regards,

--=20
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com