44、(9-12)choose all that apply
View the Exhibit and examine the details of the ORDER_ITEMS table.
Evaluate the following SQL statements:
Statement 1:
SELECT MAX(unit_price*quantity) "Maximum Order"
FROM order_items;
Statement 2:
SELECT MAX(unit_price*quantity) "Maximum Order"
FROM order_items
GROUP BY order_id;
Which statements are true regarding the output of these SQL statements? (Choose all that apply.)
A) Both statements would ignore NULL values for the UNIT_PRICE and QUANTITY columns.
B) Statement 1 would return only one row of output.
C) Both the statements would give the same output.
D) Statement 2 would return multiple rows of output.
E) Statement 1 would not return any row because the GROUP BY clause is missing.
Anser：ABD
(解析：对于 null 值，Oracle 计算的时候结果为空，但是在求最大值的时候，会忽略)
SQL> select sal*comm from emp;
SAL*COMM
----------
480000
625000
1750000
…
SQL> select max(sal*comm) from emp;
MAX(SAL*COMM)
-------------
1750000