Return Output Format From Rails PostgreSQL Query

Question

I'm writing a scope to group PageView's by created_at date and then retrieving the count for each date. Here is my scope:

scope :count_by_date, -> { group('date(created_at)').count }

This returns the counts in this format:

{Wed, 26 Aug 2020=>3, Tue, 25 Aug 2020=>8}

I'm then using this data with Chart.js to create various charts in my app. The issue I'm having is I need the hash returned from the scope to be in this format so I can use the keys and values as the charts x and y values:

{"2020-08-26"=>3, "2020-08-25"=>8}

How can I get the data back in the format I need?

Answer 1

Try the below:

Define the scope with custom select

scope :count_by_date, -> { 
  group('DATE(created_at)')
   .pluck('DATE(created_at)::varchar', 'COUNT(*)')
}

The above scope will return two dimension array like the below:

[["2020-08-11", 1], ["2020-08-24", 5], ["2020-08-14", 1]]

You need to convert the array data into hash after querying with to_h

MyModel.count_by_date.to_h