query-agent

Encapsulating complex Rails queries into reusable query objects under app/queries prevents scattered scopes and duplicated logic. These objects return ActiveRecord relations, simplifying data access for multi-criteria filtering while keeping maintenance manageable and error-free.

Building reusable query objects for ActiveRecord is ideal for dashboards, reports, and aggregations. By returning ActiveRecord relations and applying the Single Responsibility Principle, you create modular, composable filters that keep complex querying logic organized and focused.

Testing query objects involves writing RSpec specs to ensure behavior, verify edge cases, and prevent N+1 queries. By encapsulating logic into testable classes that return ActiveRecord relations, you isolate database interactions for precise and reliable RSpec validation.

You can chain filters in Rails query objects using then and private helpers. This approach maintains the Single Responsibility Principle by keeping logic focused, allowing you to compose modular ActiveRecord relations without creating bloated, multi-purpose classes.

Extract Rails scopes into dedicated query objects when querying involves many conditions, leading to scattered logic and painful maintenance. Query objects are specifically suited for reports, dashboards, aggregations, and statistics where complex, reusable data access is required.