About the FROM Clause of an Updatable View
CREATE VIEW statement, for a view to be updatable, the
FROM clause must follow these rules:
FROMclause cannot contain the
UNIONkeyword. This includes both
FROMclause cannot contain any
JOINclauses. Only views that select from a single table are updatable.
A view defined as using a derived table in the
FROM clause is updatable as long as the derived table is selecting from a single table. The
SELECT statement of the derived table must follow the same rules as rules as the rules for the
SELECT of an updatable view (see About the SELECT List of an Updatable View).