RESTRICT rejects the drop if other objects depend on the table; CASCADE drops the table together with all dependent objects.

CASCADE rejects the drop if other objects depend on the table; RESTRICT drops them too.

RESTRICT drops the table and its rows; CASCADE only drops the rows.

RESTRICT works only on views; CASCADE works only on base tables.

There is no difference — the two declarations are interchangeable.

VARCHAR(30) always occupies 30 characters, exactly like CHAR(4) occupies 4.

CHAR is for numeric codes and VARCHAR is for text; they cannot be compared.

CHAR(4) always occupies 4 characters; VARCHAR(30) uses only as many characters as needed, up to a maximum of 30.

STOP WHEN x > 5;

LEAVE LOOP;

EXIT WHEN x > 5;

BREAK;

A view selecting a subset of columns from a single base table.

A view that renames the columns of a single base table.

A view defined with GROUP BY and COUNT(*) (like StaffPropCnt).

A view filtering the rows of one table with a WHERE clause.

To save the changes made by a transaction

To undo the changes made by a transaction

To commit the changes made by a transaction

To finalize the changes made by a transaction

GRANT UPDATE

GRANT UPDATE (salary)

GRANT SELECT (salary)

GRANT UPDATE

RETURNS TRIGGER — for example CREATE OR REPLACE FUNCTION check_advisor_load() RETURNS TRIGGER ...

RETURNS VOID — trigger functions return nothing.

No RETURNS clause — CREATE TRIGGER holds the body directly.

RETURNS TABLE — trigger functions return the affected rows.