Which of the following privileges permits a user to update the comment on a sequence?（）

单项选择题Which of the following statements is used to prevent user TOM from adding and deleting data in table TAB1?（）

A.REVOKE ADD, DELETE FROM USER tom ON TABLE tab1
B.REVOKE ADD, DELETE ON TABLE tab1 FROM USER tom
C.REVOKE INSERT, DELETE FROM USER tom ON TABLE tab1
D.REVOKE INSERT, DELETE ON TABLE tab1 FROM USER tom

单项选择题A user invoking a user-defined function requires which DB2 privilege?（）

A.CALL
B.USAGE
C.EXECUTE
D.REFERENCES