[Catalyst] Group functions in Catalyst

[Dmitri Pissarenko]

Hello!

I have a table with "activities" and each of them has a certain
duration. Each activitiy is assigned to one category.

I want to create a table, in which

a) each category is shown and
b) for each category the sum of durations of its activities is shown.

In other words, I want to display the results of this query:

select SUM(duration), categories.name
FROM activities, categories
WHERE activities.categoryId = categories.id
GROUP BY activities.categoryId
ORDER BY categories.name

How can I execute this query in Catalyst and fetch the results?

TIA

Dmitri Pissarenko