Re: Database-Role settings behaviour and docs mismatch

Simon Riggs wrote:

> Whereas in process_settings() the sequence is this
>
> ApplySetting(databaseid, roleid, relsetting, PGC_S_DATABASE_USER);
> ApplySetting(InvalidOid, roleid, relsetting, PGC_S_USER);
> ApplySetting(databaseid, InvalidOid, relsetting, PGC_S_DATABASE);
>
> which looks to me like database-role specific settings are overridden by
> both user and database specific ones, in contrast to how the docs
> describe this.

Yeah, except that set_config_option contains this bit:

/*
* Ignore attempted set if overridden by previously processed setting.
* However, if changeVal is false then plow ahead anyway since we are
* trying to find out if the value is potentially good, not actually use
* it. Also keep going if makeDefault is true, since we may want to set
* the reset/stacked values even if we can't set the variable itself.
*/
if (record->source > source)
{
if (changeVal && !makeDefault)
{
elog(DEBUG3, "\"%s\": setting ignored because previous source is higher priority",
name);
return true;
}
changeVal = false;
}

> Not that bothered, but seems like the docs provide more useful behaviour
> and the code less useful.

It'd probably be worth changing the order of the ApplySetting calls so
that it doesn't look suspicious.

--
Alvaro Herrera http://www.CommandPrompt.com/
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