47、请选择最佳答案。SELECT ename, sal, comm FROM empENAME SAL COMMMARTIN 1250 1400ALLEN 1600 300ADAMS 1100CLARK 2450JAMES 950KING 5000SCOTT 3000哪条ORDER BY子句将生成所显示的输出?B) ORDER BY NVL(comm, 0) ASC NULLS LAST, enameD) ORDER BY NVL(comm, 0) ...【阅读全文】
38、请选择两项。哪两个查询将成功执行?B) SELECT COUNT(prod_id) FROM sales WHERE quantity_sold > 55000 GROUP BY prod_id;D) SELECT prod_id FROM sales WHERE quantity_sold > 55000 GROUP BY prod_id HAVING COUNT(*) > 10;【阅读全文】
36、请选择最佳答案。Name Null? TypeCUST_ID NOT NULL VARCHAR2 (6)LAST_NAME NOT NULL VARCHAR2 (50)CITY VARCHAR2 (25)可以使用哪个查询?B) SELECT * FROM customers WHERE city LIKE 'D__%';D) SELECT * FROM customers WHERE city = '%D__';...【阅读全文】