272. Which two statements are true regarding subqueries? (Choose two.)
A. The ORDER BY clause can be used in the subquery.
B. A subquery can be used in the FROM clause of a SELECT statement.
C. If the subquery returns NULL, the main query may still return result rows.
D. A subquery can be placed in a WHERE clause, GROUP BY clause, or a HAVING
clause.
E. Logical operators, such as AND, OR and NOT, cannot be used in the WHERE
clause of a subquery.
Answer: AB
来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/11312660/viewspace-719021/，如需转载，请注明出处，否则将追究法律责任。
上一篇：
047-271
下一篇：
领导者应该具备的素质
请登录后发表评论
登录
全部评论
