Double Denormalizing in Postgres
От
Robert James
Тема
Double Denormalizing in Postgres
Дата
Msg-id
CAGYyBggDaLCkMM3wcWvmy_1wwaOJrP=UwOTiWhMMehVhVvGdvQ@mail.gmail.com
Список
Дерево обсуждения
Double Denormalizing in Postgres Robert James <srobertjames@gmail.com>
Re: Double Denormalizing in Postgres Pavel Stehule <pavel.stehule@gmail.com>
Re: Double Denormalizing in Postgres David Johnston <polobo@yahoo.com>
To match the heavily denormalized format of a legacy app, I need to
take a query which gives this:
name | product | rent | own
Bob | Car | true | false
Bob | Car | false | true
Bob | Bike | false | true
Bob | Truck | true | true
and denormalize it into this:
name | rented_products | owned_products
Bob | {Car, Truck} | {Car, Truck, Bike}
I thought I could do this using array_agg, but I don't see how to do
that on a condition. In pseudocode, I'd like to do this:
SELECT
uniq(array_agg(product WHERE rent)) AS rented_products,
uniq(array_agg(product WHERE own)) AS owned_products
...
How can I achieve this? (I'm using Postgres 8.3)
В списке pgsql-general по дате отправления