3. INNER JOIN Practice Question: Join the employees and departments tables. Return the employee name and department name for all employees. Answer: SELECT e.employee_name, d.department_name FROM employees e INNER JOIN departments d ON e.department_id = d.department_id; Explanation:An INNER JOI...
Free Practice Test Instructions: Choose your answer to the question and click "Continue" to see how you did. Then click 'Next Question' to answer the next question. When you have completed the free practice test, click 'View Results' to see your results. Good luck! Answered 0 of 15 ...
For SQL interview questions that ask you to talk about the advantages or disadvantages of a certain component or tool, ensure that you list as many as you can. Also, you can make your answer to such an SQL interview question meaty by adding personal anecdotes about some of the advantages o...
试卷作答记录表exam_record(uid用户ID, exam_id试卷ID, start_time开始作答时间, submit_time交卷时间, score得分): 题目练习记录表practice_record(uid用户ID, question_id题目ID, submit_time提交时间, score得分): 请找到【昵称以『牛客』开头『号』结尾】、【成就值在1200~2500之间】,且【最近一次】【活跃(...
answer_cntint);CREATETEMPTABLEquestion_practice_detail ( idintNOTNULL, device_idintNOTNULL, question_idintNOTNULL,resultvarchar(32)NOTNULL,datedateNOTNULL);CREATETEMPTABLEquestion_detail ( idintNOTNULL, question_idintNOTNULL, difficult_levelvarchar(32)NOTNULL);INSERTINTOuser_profileVALUES(1,2138,'...
`answer_cnt` int ); CREATE TABLE `question_practice_detail` ( `id` int NOT NULL, `device_id` int NOT NULL, `question_id`int NOT NULL, `result` varchar(32) NOT NULL ); INSERT INTO user_profile VALUES(1,2138,'male',21,'北京大学',3.4,7,2,12); ...
Question 4: What happens when you create a clustered index? As explained in the answer to question 3, above, when you create a clustered index, the order of the rows in the data pages is changed. Adding a clustered index to our working example, the command is a simple one: ...
The clauses USING..JOIN..ON give more accurate results than NATURAL JOINs when joining multiple tables Oracle implicitly joins multiple tables when a NATURAL JOIN is used and hence it is a good practice to use NATURAL JOINSAnswer: C. The use of NATURAL JOINS can create Cartesian products of...
1 answerOne of the answers was accepted by the question author. OperationalError: ('HYT00', '[HYT00] [Microsoft][ODBC Driver 17 for SQL Server]Login timeout expired (0) (SQLDriverConnect)') Hi, I am encountering an issue while trying to connect to an SQL database using a Python script...
selecta.university,count(b.result) /count(distinctb.device_id)asavg_answer_cntfromuser_profile ainnerjoinquestion_practice_detail bona.device_id = b.device_idgroupbya.universityorderbya.university 4. SQL23 统计每个学校各难度的用户平均刷题数 ...