Re: doc: improve the restriction description of using indexes on REPLICA IDENTITY FULL table.

On Mon, Jul 3, 2023 at 7:45 AM Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
>
> Commit 89e46da5e5 allowed us to use indexes for searching on REPLICA
> IDENTITY FULL tables. The documentation explains:
>
> When replica identity <quote>full</quote> is specified,
> indexes can be used on the subscriber side for searching the rows. Candidate
> indexes must be btree, non-partial, and have at least one column reference
> (i.e. cannot consist of only expressions).
>
> To be exact, IIUC the column reference must be on the leftmost column
> of indexes. Does it make sense to mention that?
>

Yeah, I think it is good to mention that. Accordingly, the comments
atop build_replindex_scan_key(),
FindUsableIndexForReplicaIdentityFull(), IsIndexOnlyOnExpression()
should also be adjusted.

--
With Regards,
Amit Kapila.