how to do this in dbeaver?

Question

Research how to create queries that: 1) join multiple table; 2) use aggregate functions (e.g. sum()), and 3) “order by” statements Consider online and the text for sources. 2. Create a query that displays all of the employees who worked on a computer a. Columns should include: computer’s serial number, employee’s first name, employee’s last name b. Results should be ordered by the computer’s serial number (ascending) and then employee’s last name (ascending) Note that the query above must return at least two rows of valid data. 3. Create a query that displays the total number of labor hours spent on each computer a. Columns should include: computer’s serial number, total hours spent b. Results should be ordered by total hours (descending) Note that the query above must return at least two rows of valid data.

Answer 1

1. Joining multiple tables, using aggregate functions and ordering by statements are all common SQL concepts. Here are some resources for learning more about each:
2. Joining Multiple Tables:
3. w3schools: https://www.w3schools.com/sql/sql_join.asp
4. SQLBolt: https://sqlbolt.com/lesson/select_queries_with_joins
5. Using Aggregate Functions:
6. w3schools: https://www.w3schools.com/sql/sql_functions.asp
7. SQLBolt: https://sqlbolt.com/lesson/select_queries_with_aggregates
8. Ordering by Statements:
9. w3schools: https://www.w3schools.com/sql/sql_orderby.asp
10. SQLBolt: https://sqlbolt.com/lesson/select_queries_order_and_limit
11. Here is a query that displays all of the employees who worked on a computer, ordered by the computer's serial number (ascending) and then by employee's last name (ascending):

SELECT Computers.serial_number, Employees.first_name, Employees.last_name FROM Computers JOIN Workstations ON Computers.serial_number = Workstations.computer_serial_number JOIN Employees ON Workstations.employee_id = Employees.id ORDER BY Computers.serial_number ASC, Employees.last_name ASC;

3. Here is a query that displays the total number of labor hours spent on each computer, ordered by total hours (descending):

SELECT Workstations.computer_serial_number, SUM(Workstations.hours_worked) AS total_hours FROM Workstations GROUP BY Workstations.computer_serial_number ORDER BY total_hours DESC;

Note that these queries may need to be adjusted based on your specific database schema and data.