Re: FW: KVP table vs. hstore - hstore performance (Was: Postgres NoSQL emulation)

Salut Pierre

You wrote
> Try to create a btree index on "(bench_hstore->bench_id) WHERE
> (bench_hstore->bench_id) IS NOT NULL".

What  do you mean exactly?
=> CREATE INDEX myhstore_kps_gin_idx ON myhstore USING gin(kvps) WHERE
??? IS NOT NULL;

My table's def is:
> CREATE TABLE myhstore ( id bigint PRIMARY KEY, kvps hstore NOT NULL );
So I'm doing something like:
CREATE INDEX myhstore_kps_gin_idx ON myhstore USING gin(kvps);

Stefan


2011/5/23 Pierre C <lists@peufeu.com>:
>
>> Hi Merlin
>>
>> The analyze command gave the following result:
>>
>> On the KVP table:
>> Index Scan using kvpidx on bench_kvp (cost=0.00..8.53 rows=1 width=180)
>> (actual time=0.037..0.038 rows=1 loops=1)
>> Index Cond: (bench_id = '200000_200000'::text)
>> Total runtime: 0.057 ms
>>
>> And on the Hstore table:
>> Bitmap Heap Scan on bench_hstore (cost=32.22..3507.54 rows=1000 width=265)
>> (actual time=145.040..256.173 rows=1 loops=1)
>> Recheck Cond: (bench_hstore @> '"bench_id"=>"200000_200000"'::hstore)
>> -> Bitmap Index Scan on hidx (cost=0.00..31.97 rows=1000 width=0) (actual
>> time=114.748..114.748 rows=30605 loops=1)
>> Index Cond: (bench_hstore @> '"bench_id"=>"200000_200000"'::hstore)
>> Total runtime: 256.211 ms
>>
>> For Hstore I'm using a GIST index.
>>
>
> Try to create a btree index on "(bench_hstore->bench_id) WHERE
> (bench_hstore->bench_id) IS NOT NULL".
>
>