When writing a Rails application, how do you decide on the best indexes to add to your database? It might seem obvious, especially if you work on a project from scratch. The problem is a little harder when you come to optimize an existing codebase.
New Relic
Recently I’ve been using two methods to work out where to put indexes. Firstly I’d strongly recommend using New Relic RPM in development mode. When running your application you can visit /newrelic to get all kinds of useful information. Here you can see the most recent rails calls:
