sql-join

Question 1

What is a foreign key?

Answer 1

A FOREIGN KEY is a key used to link two tables together.

A FOREIGN KEY is a field (or collection of fields) in one table that refers to the PRIMARY KEY in another table.

Question 2

How do you join two SQL tables?

Answer 2

join clause “table name” using (“commoncolumn”)

Question 3

How do you temporarily rename columns or tables in a SQL statement?

Answer 3

we can alias their names as follows:
select "p"."name" as "product",
       "p"."category",
       "s"."name" as "supplier",
       "s"."state"
  from "products" as "p"
  join "suppliers" as "s" using ("supplierId");