Skip to content

LONDON_10/ANU THAPALIYA/Database-Homework/week-1 #51

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
anuthapaliy wants to merge 1 commit into
base: master
Choose a base branch
from
Open

LONDON_10/ANU THAPALIYA/Database-Homework/week-1 #51

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
26 changes: 26 additions & 0 deletions week-1/mandatory/2-classes-db/task.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,6 +7,32 @@ Below you will find a set of tasks for you to complete to consolidate and extend
To submit this homework write the correct commands for each question here:

```sql
1. Which rooms have a rate of more than 100.00?
cyf_hotel=# SELECT room_no, rate, room_type FROM rooms WHERE rate > 100;
2. List the reservations that have a checkin date this month and are for more than three nights.
cyf_hotel=# SELECT id, cust_id, room_no, checkin_date, checkout_date, no_guests, booking_date, checkout_date - checkin_date AS duration_of_stay FROM reservations WHERE EXTRACT(MONTH FROM checkin_date) = EXTRACT(MONTH FROM current_date) AND checkout_date - checkin_date > 3;
3. List all customers from cities that begin with the letter 'M'.
SELECT * FROM Customers WHERE City LIKE 'M%';

Insert some new data into the room_types and rooms tables, querying after each stage to check the data, as follows:
4. Make a new room type of PENTHOUSE with a default rate of £185.00
cyf_hotel=# INSERT INTO room_types (room_type, def_rate) VALUES ('PENTHOUSE', 185.00);
5. Add new rooms, 501 and 502 as room type PENTHOUSE and set the room rate of each to the default value (as in the new room type).
INSERT INTO rooms (room_no, rate, room_type) VALUES (501, (SELECT def_rate FROM room_types WHERE room_type = 'PENTHOUSE'), 'PENTHOUSE'),(502, (SELECT def_rate FROM room_types WHERE room_type='PENTHOUSE'), 'PENTHOUSE');
6. Add a new room 503 as a PREMIER PLUS type similar to the other PREMIER PLUS rooms in the hotel but with a room rate of 143.00 to reflect its improved views over the city.
INSERT INTO rooms (room_no, rate, room_type) VALUES (503, 143.00, 'PREMIER PLUS');
To check if room no. 503 been added or not i have checked using SELECT room_no, rate, room_type FROM rooms WHERE room_no = 503;yes its worked.
7. The hotel manager wishes to know how many rooms were occupied any time during the previous month - find that information.
SELECT COUNT(DISTINCT room_no) AS occupied_rooms FROM reservations WHERE (checkin_date <=date_trunc('month',current_date) - interval '1 day') AND (checkout_date >= date_trunc('month', current_date - interval '1 month'));
8. Get the total number of nights that customers stayed in rooms on the second floor (rooms 201 - 299).
SELECT SUM (checkout_date - checkin_date) AS total_nights FROM reservations WHERE room_no BETWEEN 201 AND 299;
9. How many invoices are for more than £300.00 and what is their grand total and average amount?
SELECT COUNT(*) AS num_invoices, SUM(total) AS grand_total, AVG(total) AS average_total FROM invoices WHERE total > 300.00;
10. Bonus Question: list the number of nights stay for each floor of the hotel (floor no is the hundreds part of room number, e.g. room **3**12 is on floor **3**)
SELECT FLOOR(room_no / 100) AS floor_number, SUM(checkout_date - checkin_date) AS total_nights FROM reservations WHERE room_no BETWEEN 101 AND 499 GROUP BY FLOOR(room_no / 100) ORDER BY floor_number;





```
Expand Down