你可能感興趣的試題

You are currently located in Singapore and have connected to a remote database in Chicago. You issue the following command:SQL> SELECT ROUND (SYSDATE-promo_begin_date, 0) FROM promotions WHERE (SYSDATE-promo_begin_date)/365 >2;PROMOTIONS is the public synonym for the public database link for the PROMOTIONS table. What is the outcome?（）

A.an error because the ROUND function specified is invalid
B.an error because the WHERE condition specified is invalid
C.number of days since the promo started based on the current Chicago date and time
D.number of days since the promo started based on the current Singapore date and time

單項(xiàng)選擇題

Which statement is true regarding subqueries?（）

A.The LIKE operator cannot be used with single-row subqueries
B.The NOT IN operator is equivalent to IS NULL with single-row subqueries
C.=ANY and =ALL operators have the same functionality in multiple-row subqueries
D.The NOT operator can be used with IN, ANY, and ALL operators in multiple-row subqueries