Question

I have a record set that includes a date field, and want to determine how many unique dates are represented in the record set.

Something like:

Record.find(:all).date.unique.count  

but of course, that doesn’t seem to work.

Answer 1

What you’re going for is the following SQL:

SELECT COUNT(DISTINCT date) FROM records 

ActiveRecord has this built in:

Record.count('date', :distinct => true)