Re: Hash Functions

On 06/02/2017 05:47 AM, Robert Haas wrote:
> On Fri, Jun 2, 2017 at 1:24 AM, Jeff Davis <pgsql(at)j-davis(dot)com> wrote:
>> 2. I basically see two approaches to solve the problem:
>> (a) Tom suggested at PGCon that we could have a GUC that
>> automatically causes inserts to the partition to be re-routed through
>> the parent. We could discuss whether to always route through the
>> parent, or do a recheck on the partition constrains and only reroute
>> tuples that will fail it. If the user gets into trouble, the worst
>> that would happen is a helpful error message telling them to set the
>> GUC. I like this idea.
>
> Yeah, that's not crazy. I find it a bit surprising in terms of the
> semantics, though. SET
> when_i_try_to_insert_into_a_specific_partition_i_dont_really_mean_it =
> true?

Maybe
SET partition_tuple_retry = true;
-or-
SET partition_tuple_reroute = true;
?

I like the idea of only rerouting when failing constraints although I
can envision where there might be use cases where you essentially want
to re-partition and therefore reroute everything, leading to:

SET partition_tuple_reroute = (none | error | all);

Joe

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