CODEWITHSUNDEEP
sqlruby-on-railspostgresqlactiverecord
Sam Stern
Sam Stern

Reputation: 25134

How to combine many SQL queries into one?

I have two tables relevant to this question.

The first is Company which has_many Taps. Each Tap has a Date field that states the date when it was created (different than created_at for reasons irrelevant here).

I want to plot the frequency of Taps for a company over time, grouping by day. That means for my 30-day graph, I am currently making a separate SQL query for each Date in my range to get app taps where :tapped_time = {some date} and :company_id = {id of the company}.

How can I get the number of Taps for a Company on each day in a consecutive range without making a separate query for each day?

I am using Ruby on Rails, so I don't need raw SQL I just need some help with my ActiveRecord magic.

Upvotes: 1

Views: 545

Answers (1)

Mike Sherrill 'Cat Recall'
Mike Sherrill 'Cat Recall'

Reputation: 95562

In SQL, you'd group by date if you're querying for a single company, by date and company if you're querying for multiple companies at one time.

ActiveRecord has a group method for that.

Upvotes: 2

Related Questions