Re: [WIP]Vertical Clustered Index (columnar store extension) - take2

On Wed, 2025-06-25 at 12:22 +1000, Peter Smith wrote:
> Hi.
>
> Here are the latest v9* patches. These have following changes:
>
> 0001
> -  fixes some of the minor quirks reported by Tomas [1].
>
> 0002
> - fixes to added address some of Timur's feedback/patches [2]
> - test code updated to remove unsupported type
> - test code updated to remove dynamic costings
>
Hello Peter!

Thanks for updates.
I was trying to move some code from Postgres core patch to contrib/vci.
Started with moving VCI options from StdRdOptions struct and
reloptions.c, reloptions.h files into contrib/vci like Tomas suggested
earlier. Getting new relopt kind using add_reloption_kind() instead of
hardcoded RELOPT_KIND_VCI and so on, just like in contrib/bloom.

During this work I've found that those VCI-specific options,
"vci_column_ids" and "vci_dropped_column_ids", are only read in case
vci_IsExtendedToMoreThan32Columns() is true. And
vci_IsExtendedToMoreThan32Columns() itself checks if vci_column_ids
option is non-empty string to return true. AFAIK no one sets those
options and vci_IsExtendedToMoreThan32Columns() always returns false.

There are comments in code mentioning that one can create VCI index
with more than 32 columns using vci_create(). However, there is no such
a function anywhere. I guess it is now impossible to create VCI index
with more than 32 (INDEX_MAX_KEYS) columns. Maybe the options were used
to store column information for indexes created with vci_create() but
this function has gone.

So, giving the ideas above, can we remove those vci_column_ids,
vci_dropped_column_ids options and all the code that assumes
vci_IsExtendedToMoreThan32Columns() to be true? This would make core
patch a bit shorter, specifically there will be no changes in
reloptions.{c,h} files and no changes in StdRdOptions struct in rel.h.

--
Regards,
Timur Magomedov