The UPDATE Statement

The general form of the UPDATE statement is:

UPDATE <table> [<alias>]
SET <field>=<expression>, <field>=<expression>, ...
WHERE <condition>;

All the records in the specified table which match the condition are updated. If the condition is omitted, all the records are updated.

For each record, the specified fields are set equal to the specified expressions (which may refer to the same or other fields of the table). Fields not specified in the statement are unchanged.

If any of the expressions refer to any of the fields of the table, the values used in calculating the expressions are the value that the fields had before any of the updates were made.

Note that the COMMIT WORK statement must be executed before the updates are finally made.