Question

In what situations should be used Model.where or Model.find() ? Everywhere is information on the differences, but what is a recommendation for their use?

Answer 1

where doesn’t actually fetch anything – it returns an ActiveRecord::Relation scoped with the conditions you’ve just specified. This means you can chain it with stuff: more calls to where, joins, limit etc.

find on the other can executes the query and returns an array or an object (depending on whether you do find :all or find :first, so you can’t chain stuff on the back of it.

You can pass conditions, joins etc. to find but doing so will become deprecated. You don’t really ever need to call find since you either let the ActiveRecord::Relation turn itself into an array when it needs to or call all/first/last on the relation, which achieves the same thing that calling find would do.

About the only thing find is handier for is when you have an id (or array of ids) and want to load the corresponding model objects.