Re: On partitioning

On Wed, Dec 10, 2014 at 7:25 PM, Amit Langote
<Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> In heap_create(), do we create storage for a top level partitioned table (say, RELKIND_PARTITIONED_TABLE)? How about a partition that is further sub-partitioned? We might allocate storage for a partition at some point and then later choose to sub-partition it. In such a case, perhaps, we would have to move existing data to the storage of subpartitions and deallocate the partition's storage. In other words only leaf relations in a partition hierarchy would have storage. Is there such a notion within code for some other purpose or we'd have to invent it for partitioning scheme?

I think it would be advantageous to have storage only for the leaf
partitions, because then you don't need to waste time doing a
zero-block sequential scan of the root as part of the append-plan, an
annoyance of the current system.

We have no concept for this right now; in fact, right now, the relkind
fully determines whether a given relation has storage. One idea is to
make the leaves relkind = 'r' and the interior notes some new relkind.

--
Robert Haas
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