MySQL Create an advanced junction

The two main reasons why SQL allows tables to be aliased are:

• Shorten SQL statements;
• Allows the same table to be used multiple times in a single SELECT statement;

We use aliases to represent a table that corresponds to the previous one:

Self-coupling

Question: If you know that a product ID produced by a manufacturer is problematic for dtntr, you need to find all the other products produced by that manufacturer from the database.

The following SELECT statement can find all the products produced by the vend_id:

Now look at the same query that uses the junction: