Question

I have 3 tables employees, managers, users. I want to insert value 1 into users column is_manager only if the id from employees matches id from managers. id is primary key in employees and primary and foreign key in managers.

Any help would be appreciated. Thanks

Answer 1

Either

UPDATE users 
INNER JOIN managers ON users.id=managers.id
SET users.is_manager=1

or

UPDATE users SET is_manager=1
WHERE id IN (
  SELECT id FROM managers
)

will do. I recommend the latter for better readability.