That is terrible advice. 1. Numeric based Primary Key Lookups are some of the fastest operations on modern databases. 2. "Slugs", are a set of strings, which o

That is terrible advice. 1. Numeric based Primary Key Lookups are some of the fastest operations on modern databases. 2. "Slugs", are a set of strings, which occupy more memory, space, now you have to come up with some way to make them unique. If you are building a CMS, sure, SEO is important. If you are building a line of business application, no. 3. Just checked, Google and Facebook expose numeric based identifiers. My Facebook Business ID is numeric, my Google Analytics ID is numeric with a prefix on it. 4. There are plenty of libraries out there that will take a numeric value, convert it to a small alphanumeric value with a check digit. 5. No end user cares about URLs (except for SEO). Your business user is not going to navigate your application by going to myapp/settings, they are going to click on the gear icon.