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Is there a compact way with ActiveRecord to query for what id it's going to use next if an object was going to be persisted to the database? In SQL, a query like this would look something like:
SELECT max(id) + 1 FROM some_table; 
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ActiveRecord::Base indicates that the ActiveRecord class or module has a static inner class called Base that you're extending.
The additional difference between find() and find_by() is that find could only be used to search by primary key (usually the 'id') while the find_by() requires and searches by attribute (either passed as hash like Employee. find_by(name: 'Mike') or using the Employee.
Active Record allows you to validate the state of a model before it gets written into the database. There are several methods that you can use to check your models and validate that an attribute value is not empty, is unique and not already in the database, follows a specific format, and many more.
What is ActiveRecord? ActiveRecord is an ORM. It's a layer of Ruby code that runs between your database and your logic code. When you need to make changes to the database, you'll write Ruby code, and then run "migrations" which makes the actual changes to the database.
Here is slightly modified Taryn East's version:
Model.maximum(:id).next While accepting fig's answer I might want to draw your attention to a small thing. If you are getting the next ID to set to a particular record before saving, I think its not a good idea.
because as an example in a web based system
I'm not sure you want the last id to do what I'm thinking here, But if so this is just to draw your attention.
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