Re: On partitioning

On Wed, Dec 10, 2014 at 7:25 PM, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> In heap_create(), do we create storage for a top level partitioned table (say, RELKIND_PARTITIONED_TABLE)? How about
apartition that is further sub-partitioned? We might allocate storage for a partition at some point and then later
chooseto sub-partition it. In such a case, perhaps, we would have to move existing data to the storage of subpartitions
anddeallocate the partition's storage. In other words only leaf relations in a partition hierarchy would have storage.
Isthere 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
EnterpriseDB: http://www.enterprisedb.com
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