Re: tid_blockno() and tid_offset() accessor functions

Hi,

On 2026-03-11 14:48:08 -0700, Masahiko Sawada wrote:
> On Fri, Feb 27, 2026 at 10:59 AM Ayush Tiwari
> <ayushtiwari(dot)slg01(at)gmail(dot)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 analysis) 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, and 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.

That just seems less readable and harder to find to me. I think it'd also
make the amount of required code noticeably larger?

Greetings,

Andres