Always, always, always use an “id” as the primary key for your relational database tables
where that “id” is a database sequence generated value. And if that
table has a relationship with another table then make sure your column name is :
“tablename_id”. This is the common wisdom in using Ecto (or really any modern
relational library that attempts to help you with talking to your relational
database). But although there may be many people who tell you it can’t be done any
other way that information is not true and the facts are laid out in the Ecto
documentation (which is really good as is the case with most of the Elixir library
doc that I’ve had to read).