| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> |
| Cc: | Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Stephen Frost <sfrost(at)snowman(dot)net>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: our checks for read-only queries are not great |
| Date: | 2020-01-12 17:06:06 |
| Message-ID: | 14123.1578848766@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> writes:
> Perhaps it would be good to consider this question:
> Do we call something "read-only" if it changes nothing, or do we call it
> "read-only" if it is allowed on a streaming replication standby?
> The first would be more correct, but the second may be more convenient.
Yeah, this is really the larger point at stake. I'm not sure that
"read-only" and "allowed on standby" should be identical, nor even
that one should be an exact subset of the other. They're certainly
by-and-large the same sets of operations, but there might be
exceptions that belong to only one set. "read-only" is driven by
(some reading of) the SQL standard, while "allowed on standby" is
driven by implementation limitations, so I think it'd be dangerous
to commit ourselves to those being identical.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Peter | 2020-01-12 18:36:33 | Re: 12.1 not useable: clientlib fails after a dozen queries (GSSAPI ?) |
| Previous Message | Laurenz Albe | 2020-01-12 16:25:38 | Re: our checks for read-only queries are not great |