Re: Read-only tables to avoid row visibility check

Seamus Abshere <seamus@abshere.net> writes:
> Being able to tell postgres that our table is "Read Only" has imaginary
> mystical properties for me, first and foremost being able to count
> against indexes without ever hitting the disk.

>> ​If the system is working properly then a READ ONLY table in fact should be able to use Index Only Scans without the
hackof a DBA telling it that said table is READ ONLY.​ 

> So this should happen already?

Yeah.  Index-only scans will work if all (or at least most) of the table
hasn't been modified since the last VACUUM.  If we had a READ ONLY
property, I do not think it would affect that logic at all; it would just
prevent future mods going forward.  Which, as noted, you could already do
by revoking suitable privileges.

            regards, tom lane