Hello
my opinion:
@1 can be faster for access to last items with index
@2 can be more effective about data files length allocation
@1 or @2 - it depends on number of prices per product. For small
number (less 100) I am strong for @2 (if speed is important).
Personally prefer @2.
Pavel
2010/11/16 Louis-David Mitterrand <vindex+lists-pgsql-performance@apartia.org>:
> Hi,
>
> I have to collect lots of prices from web sites and keep track of their
> changes. What is the best option?
>
> 1) one 'price' row per price change:
>
> create table price (
> id_price primary key,
> id_product integer references product,
> price integer
> );
>
> 2) a single 'price' row containing all the changes:
>
> create table price (
> id_price primary key,
> id_product integer references product,
> price integer[] -- prices are 'pushed' on this array as they change
> );
>
> Which is bound to give the best performance, knowing I will often need
> to access the latest and next-to-latest prices?
>
> Thanks,
>
> --
> Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-performance
>