Re: Suggestion for aggregate function

Manfred Koizar <mkoi-pg(at)aon(dot)at> writes:

> Greg, we already have this feature, just the syntax is a bit different :-)
>
> SELECT DISTINCT ON (item_id) item_id,
> price AS lowest_price,
> store_id AS lowest_price_store
> FROM items_for_sale
> WHERE item_category = ?
> ORDER BY item_id, price

Neat! I hadn't seen this. I would have liked to have had that feature on
Oracle! (Please don't tell me I did, I went through such pains to work around
not having it.)

Would this query be efficient if there's an index on item_id, price ? That is,
would it know to do an index scan and be able to skip to the next item_id in
the index as soon as a price was found?

--
greg