Re: BUG #17385: "RESET transaction_isolation" inside serializable transaction causes Assert at the transaction end

On Wed, Jun 29, 2022 at 3:48 PM Michael Paquier <michael@paquier.xyz> wrote:
>
> On Tue, Jun 28, 2022 at 03:58:41PM +0900, Masahiko Sawada wrote:
> > Agreed. I've attached an updated patch.
>
> +#define GUC_NO_RESET         0x400000  /* not support RESET and save */
>
> It is a bit sad to see this new flag with this number, separated from
> its cousin properties.  Could it be better to reorganize the flag
> values and give more room to the properties?  The units for memory and
> time could go first, for example.

It seems a good idea, I'll update it in the next version patch.

>
> +CREATE FUNCTION errfunc() RETURNS int LANGUAGE SQL AS 'SELECT 1'
> +SET transaction_read_only = on; -- error
> +ERROR:  parameter "transaction_read_only" cannot be reset
> Well, this is confusing when setting a GUC_NO_RESET in the context of
> GUC_ACTION_SAVE.

Right, how about "parameter %s cannot be set"?

> By the way, what about "seed"?

Resetting seed is no-op so it might be better to throw an error when
resetting the seed rather than doing nothing silently.

Regards,

--
Masahiko Sawada
EDB:  https://www.enterprisedb.com/