Re: truncate trigger for foreign data wrappers

On Fri, Aug 5, 2016 at 2:04 PM, Andres Freund <andres@anarazel.de> wrote:
> On 2016-08-05 13:32:18 -0400, Robert Haas wrote:
>> I think if we're going to add support utility commands on foreign
>> tables, we ought to think about all of the different utility commands
>> that someone might want and what exactly we want the behavior to be.
>
>> For example, consider CLUSTER or CREATE INDEX or VACUUM or ANALYZE.
>> We might interpret TRUNCATE or CLUSTER as a request to dispatch the
>> same request for the remote side, but ANALYZE can't mean that: it has
>> to mean gather local statistics.  And what if the other side is not PG
>> and supports other operations that we don't have, like OPTIMIZE TABLE
>> or DISENGAGE FTL?
>
> That's not really comparable imo - we don't have triggers for those
> locally either. For better or worse we've decided that TRUNCATE is more
> like DML than DDL.

I agree, but I still think it's weird if foreign tables support
TRUNCATE itself not but triggers on TRUNCATE.  And I don't want to
start supporting TRUNCATE itself without a bit more thought about
where we go from there.

-- 
Robert Haas
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