> It means that everything a relational database is capable of (from CS theory) can be done with a single column of values per table. Note that each such table also has a "column" of primary keys

So, in other words, it's a two column table (“primary key” aren't some kind of virtual column, either in concrete databases or in relational theory.)

Calling a database with two columns one of which is the primary key a one-column table is...just wrong.