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Updating Records

Michael Xue
Christopher McCulloh
2.14.06

So we use the "update" command with a "where" clause:

update person set address = '234 Nice Street', city = 'Indianapolis', country = 'USA', gender = 'M' where person_id = 1 ;

Now let's see what happens if we don't use a where clause, and let's see what happens when you try to set something to an invalide date.

So first the invalid date:

update person set birth_date = 'DEC-24-2006' where person_id = 1 ;

That caused it to give a warning, and then set his birthday to 0000-00-00

Now let's get rid of the where clause and see what happens. It changes everyone's birthday to 0000-00-00.

Oracle won't let you insert incorrect things at all. MySQL will just warn you and then insert a default value.

Now, update the rows and set the birthdate back to a valid date. Use a where clause.

update person set birth_date = '1984-03-27' where person_id = 1 ; update person set birth_date = '1983-09-23' where person_id = 2 ;