Syntax:
ALTER
    [ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}]
    [DEFINER = { user | CURRENT_USER }]
    [SQL SECURITY { DEFINER | INVOKER }]
    VIEW view_name [(column_list)]
    AS select_statement
    [WITH [CASCADED | LOCAL] CHECK OPTION]

This statement changes the definition of a view, which must exist. The
syntax is similar to that for CREATE VIEW and the effect is the same as
for CREATE OR REPLACE VIEW. See [HELP CREATE VIEW]. This statement
requires the CREATE VIEW and DROP privileges for the view, and some
privilege for each column referred to in the SELECT statement. As of
MySQL 5.1.23, ALTER VIEW is allowed only to the definer or users with
the SUPER privilege.

URL: http://dev.mysql.com/doc/refman/5.1/en/alter-view.html

