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 an existing view. The syntax is similar to that for CREATE VIEW. See Section 19.2, “CREATE VIEW Syntax”. This statement requires the CREATE VIEW and DROP privileges for the view, and some privilege for each column referred to in the SELECT statement.

This statement was added in MySQL 5.0.1. The DEFINER and SQL SECURITY clauses may be used as of MySQL 5.0.16 to specify the security context to be used when checking access privileges at view invocation time. For details, see Section 19.2, “CREATE VIEW Syntax”.