OCP 11g题库详解：1Z0-051-059题

OCP 11g题库详解：1Z0-051-059题，完整题库请点击这里联系老师咨询了解

59. View the Exhibit and examine the data in the PRODUCTS table.

You need to display product names from the PRODUCTS table that belong to the 'Software/Other '

category with minimum prices as either $2000 or $4000 and no unit of measure.

You issue the following query:

SQL>SELECT prod_name, prod_category, prod_min_price

FROM products

WHERE prod_category LIKE '%Other%' AND (prod_min_price = 2000 OR

prod_min_price = 4000) AND prod_unit_of_measure <> '';

Which statement is true regarding the above query?

A. It executes successfully but returns no result.

B. It executes successfully and returns the required result.

C. It generates an error because the condition specified for PROD_UNIT_OF_MEASURE is not valid.

D. It generates an error because the condition specified for the PROD_CATEGORY column is not valid.

Answer: A

试题解析：

因为prod_unit_of_measure <> ''该条件为假，’’相当于NULL，所以会导致该WHERE子句里所有AND连接的值为假，

虽然执行成功但不会返回结果，正确的条件应该是prod_unit_of_measure is not null。