Ruby on Rails | Postgres : How to find records with status (which is calculated based on...

I have a listing page of schools where I have to list the name and status of the school. The status is calculated based on the student's status.

Here is my models...

class School < ActiveRecord::Base
has_many :students
has_many :teachers
end

class Student < ActiveRecord::Base
belongs_to :school

enum status: {
active: 'active',
suspended: 'suspended'
}
end


So, the idea is list the school name and school status as

1. school status is active when at least one student is in active state.
2. school status is suspended when no active student but student record exists.
3. school status is closed when there is no students record against school.

I am trying hard to find the query to get the data like I wanted. Since this is a has_many I am finding it difficult for me. I use postgresql database.

Any help will be appreciated.

Note: I need the sql query to find this. (something like combining two tables, calculating the status based on the condition)



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