To find records in one table that aren't in another, you can use a LEFT JOIN and check for NULL values in the right-side table. Here's an example using two tables, Pinterest employees and Pinterest managers: SELECT * FROM pinterest_employees LEFT JOIN pinterest_managers ON pinterest_employees.id = pinterest_managers.id WHERE pinterest_managers.id IS NULL; This query returns all rows from Pinterest employees where there is no matching row in managers based on the id column. You can also use the EXCEPT operator in PostgreSQL and Microsoft SQL Server to return the records that are in the first table but not in the second. Here is an example: SELECT * FROM pinterest_employees EXCEPT SELECT * FROM pinterest_managers This will return all rows from employees that are not in managers. The EXCEPT operator works by returning the rows that are returned by the first query, but not by the second. ---