B. when a ROLLBACKcommand is executed

C. when a PL/SQLanonymous block is executed

D. when a datadefinition language ( DDL) statement is executed

E. when a TRUNCATEstatement is executed after the pending transaction

Answer: BDE

解析：

A选项，delete操作后可以回滚，所以事务未完成

C选项，pl/sql匿名块执行后，也可以回滚

174. Which statement istrue regarding transactions (Choose all that apply.)

A. A transaction canconsist only of a set of DML and DDL statements.

B. A p art or an entiretransaction can be undone by using ROLLBACK command .

C. A transactionconsists of a set of DML or DCL statements.

D. A part or an entiretransaction can be made permanent with a COMMIT.

E. A transaction canconsist of only a set of queries or DML or DDL statements.

Answer: BC

解析：

A选项，事务只能是dml或DCL语句组成

D选项，违反事务原子性

E选项和A选项原因一样

175. Which twostatements are true regarding savepoints (Choose two.)

A. Savepoints are effectiveonly for COMMIT.

B. Savepoints may beused to ROLLBACK.

C. Savepoints can beused for only DML statements.

D. Savepoints areeffective for both COMMIT and ROLLBACK.

E. Savepoints can beused for both DML and DDL statements.

Answer: BC

解析：
A选项，应该是rollback

D选项和C选项原因一样

E选项，不能用于ddl