第 68 题 (多选题)： Table ORDER_ITEMS contains columns ORDER_ID, UNIT_PRICE and QUANTITY, of data type NUMBE.Examine these SQL statement. Which two statements are true.

A. Statement 1 returns only one row of output. B. Statement 2 may return multiple rows of output. C. Statement 2 returns only one row of output. D. Both the statements give the same output. E. Both statements will return NULL if either UNIT_PRICE or QUANTITY contains NULL 显示答案