Tom Lane schrieb am 11.11.2014 um 17:08:
>> Does this mean that pg_get_expr() selects additional data from the table,
>> instead of just using the values that are provided by the caller?
>
> No, it means it depends on backend code that is also used when accessing
> the table "for real", and that code doesn't work safely without a lock.
> (In particular, a lot of what ruleutils.c does ultimately reduces to
> catalog cache lookups, and we can *not* allow stale data in those caches.)
Ah! Understood. Thanks for the explanation.
Thomas
