Free practice question Want more SQL interview prep? Try your hand with this free practice question: Cocoa Confections is a small bakery that sells brownies, cookies, pies, and other delicious treats to customers online. It keeps records of all of its online sales in an SQL database that is...
This is a good question to get some practice with SQL joins, so see if you can come up with the solution. Now, what tables should we use for the join? We know that the customer ID of Samsonic is 4, so we can use that information and do a simple join with the salesperson and ...
I skipped the introductory section, and jumped straight to intermediate/advanced problems. The book uses an entirely different practice database, and a completely new set of 40 problems. It also assumes that you've completed the original SQL Practice Problems recently, so the concepts are fresh i...
Each question comes with a perfectly written answer inline, saving your interview preparation time. It also covers practice problems to help you understand the basic concepts of SQL. We've divided this article into the following sections: SQL Interview Questions PostgreSQL Interview Questions In the ...
Here are the modified SQL queries with each question and its corresponding answer separated: 11. Find the third maximum salary from the “salaries” table without using the LIMIT clause. Answer: SELECT salary FROM salaries ORDER BY salary DESC LIMIT 1 OFFSET 2; 12. List the employees who ...
44. With respect to the query and the table structure given below,answer the question.SQL> DESC employees Name Null? Type --- --- --- EMPLOYEE_ID NOT NULL NUMBER(6) FIRST_NAME VARCHAR2(20) LAST_NAME NOT NULL VARCHAR2(25) EMAIL NOT NULL VARCHAR2(25) PHONE_NUMBER VARCHAR2(20) ...
Since the question asked for the number of user_ids and not the user_id’s itself we useCOUNTin the outer query. Query 5 We are given a subscription table which consists of subscription start and end date for each user. We need to write a query that returns true/false for each user ...
Or “List the different types of JOINs!” That’s a stupid type of SQL tech assessment — as it focuses on theory and not on practice. Still, some companies… you know. Take-home SQL assignment. You get a more complex task and you’ll have to write multiple SQL queries to solve it...
A DB query is a code written in order to get the information back from the database. Query can be designed in such a way that it matched with our expectation of the result set. Simply, a question to the Database.What is subquery?
13. 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; ...