The UPDATE command is used to change data that is stored in one or more records.

 Single Column Update

UPDATE customers
SET email='gandalf45@yahoomail.co.uk'
WHERE customerID = 1

Multiple Column Update

UPDATE customers
SET emai ='gandalf45@yahoomail.co.uk', location='The West'
WHERE customerID = 1

DANGER!

Using an UPDATE command without a WHERE will update all records

UPDATE customers
SET email = 'gandalf45@yahoomail.co.uk'