On 4.12.2011 17:10, Tom Lane wrote:
> Tomas Vondra <tv(at)fuzzy(dot)cz> writes:
>> Anyway, the code I posted does not fail because of pg_stat_activity, it
>> fails because it attempts for find the dbname/username for the backends
>> (read from pg_stat_activity).
> 
> Well, get_database_name tries to do a syscache lookup, and the syscache
> infrastructure isn't working yet.  It is possible to read a shared
> catalog at this stage, but you have to use lower-level access mechanisms
> --- for an example with some comments, look at GetDatabaseTuple in
> postinit.c.

Great, this seems to work perfectly.

What about the pg_stat_activity - is it safe to access that from auth
hook or is that just a coincidence that it works (and might stop working
in the future)?

Tomas

In response to

• Re: cannot read pg_class without having selected a database / is this a bug? at 2011-12-04 16:10:17 from Tom Lane

Responses

• Re: cannot read pg_class without having selected a database / is this a bug? at 2011-12-04 21:26:41 from Tom Lane

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