Is an index needed for a primary key in SQLite?

Question

When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an

Answer 1

A database will always silently create an index for a unique primary key so it can internally check it is unique efficiently.

Having created it, it will use it when necessary.

It won't, of course, always be clustered, and you specify usually in the schema if you want it to be.