On 2019/03/05 11:59, Amit Langote wrote:
> On 2019/03/05 8:47, Andres Freund wrote:
>> Hi,
>>
>> In the pluggable storage patch [1], one thing that I'm wondering about
>> is how exactly to inherit the storage AM across partitions. I think
>> that's potentially worthy of a discussion with a wider audience than I'd
>> get in that thread. It seems also related to the recent discussion in [2]
>>
>> Consider (excerpted from the tests):
>>
>> CREATE TABLE tableam_parted_heap2 (a text, b int) PARTITION BY list (a)
>> USING heap2;
>>
>> SET default_table_access_method = 'heap';
>> CREATE TABLE tableam_parted_a_heap2 PARTITION OF tableam_parted_heap2 FOR
>> VALUES IN ('a');
>>
>> SET default_table_access_method = 'heap2';
>> CREATE TABLE tableam_parted_b_heap2 PARTITION OF tableam_parted_heap2 FOR
>> VALUES IN ('b');
>>
>> CREATE TABLE tableam_parted_c_heap2 PARTITION OF tableam_parted_heap2 FOR
>> VALUES IN ('c') USING heap;
>> CREATE TABLE tableam_parted_d_heap2 PARTITION OF tableam_parted_heap2 FOR
>> VALUES IN ('d') USING heap2;
>>
>> It seems pretty clear that tableam_parted_heap2, tableam_parted_d_heap2
>> would be stored via heap2, and tableam_parted_c_heap2 via heap.
>>
>> But for tableam_parted_a_heap2 tableam_parted_b_heap2 the answer isn't
>> quite as clear. I think it'd both be sensible for new partitions to
>> inherit the AM from the root, but it'd also be sensible to use the
>> current default.
>
> Given that many people expected this behavior to be the sane one in other
> cases that came up, +1 to go this way.
Reading my own reply again, it may not be clear what I was +1'ing. I
meant to vote for the behavior that David described in his reply.
Thanks,
Amit
