Update (SQL)

An SQL UPDATE statememt changes data in a record (or records) in a relational database system.

UPDATE statement has the following form:

UPDATE table_name SET column_name = value [WHERE criteriavariable = value]

For the UPDATE to be successfull, the user must have data manipulation privileges (UPDATE privilege) over the table or column, the updated value must not conflict with all the applicable constraints (such as primary keys, unique indexes , CHECK constraints, and NOT NULL constraints).

Example :

UPDATE phone_book SET number='+3592434343' WHERE name='Johnson, Albert J.'