What is the difference between `INNER JOIN` and `SEMI JOIN` in SQL?

Question

Advanced SQL Developer — Medium

What is the difference between `INNER JOIN` and `SEMI JOIN` in SQL?

Accepted Answer

The key difference between INNER JOIN and SEMI JOIN is that INNER JOIN returns all matching columns from both tables and can produce duplicates, while SEMI JOIN returns rows from the left table only once for each row that has a match — no columns from the right table are returned.