单项选择题
ORACLE使用哪个系统参数设置日期的格式?()
A.nls_language
B.nls_date
C.nls_time_zone
D.nls_date_format
相关考题
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单项选择题
观察customers表的表结构,其中CUSTOMER_ID是表的主键。下列哪个选项能够查询出“Los Angeles”和“San Francisco”的城市地址(city_address),以及每个城市里顾客的数量?()
A.SELECT city_address,COUNT(*)FROM customers WHERE city_address IN (’Los Angeles’,’San Francisco’);
B.SELECT city_address,COUNT(*)FROM customers WHERE city_address IN (’Los Angeles’,’San Francisco’)GROUP BY city_address;
C.SELECT city_address,COUNT(customer_id)FROM customers WHERE city_address IN (’Los Angeles’,’San Francisco’)GROUP BY city_address,customer_id;
D.SELECT city_address,COUNT(customer_id)FROM customers GROUP BY city_address IN (’Los Angeles’,’San Francisco’); -
单项选择题
观察employees表的表结构,经理要求你创建一个视图EMP_VU,该视图允许用户通过视图向表中插入数据,选项中符合要求的是()。
A.CREATE VIEW emp_vu AS SELECT employee_id,emp_name,department_id FROM employees WHERE mgr_id IN (102,120);
B.CREATE VIEW emp_vu AS SELECT employee_id,emp_name,job_id,department_id FROM employees WHERE mgr_id IN (102,120);
C.CREATE VIEW emp_vu AS SELECT department_id,SUM(sal)TOTALSAL FROM employees WHERE mgr_id IN (102,120)GROUP BY department_id;
D.CREATE VIEW emp_vu AS SELECT employee_id,emp_name,job_id,DISTINCT department_id FROM employees; -
单项选择题
关于右外连接查询的说法不正确的是()。
A.两表进行右外连接查询和左外连接查询查询出的结果都是一样的
B.右外连接查询是以右侧的表为主表
C.右外连接查询可以和左外连接查询相互转换
D.右外连接查询查询时右表中的记录会全部显示