KeithBremer · maxbmaapc · Aug 26, 2023 · Aug 28, 2023 · Aug 28, 2023 · Aug 28, 2023
diff --git a/README.md b/README.md
@@ -1 +1,189 @@
-# Databases-Homework
+# Databases-Homework
+
+### Tasks
+
+1.  Which rooms have a rate of more than 100.00?
+
+PREMIER
+PREMIER PLUS
+FAMILY
+
+2.  List the reservations that have a checkin date this month and are for more than three nights.
+
+cyf_hotels=# select cust_id, room_no, checkout_date - checkin_date as nights from reservations where checkin_date > '2023-08-01' and (checkout_date - checkin_date) > 2;
+cust_id | room_no | nights
+---------+---------+--------
+4 | 312 | 3
+131 | 301 | 6
+117 | 101 | 4
+119 | | 5
+64 | | 3
+51 | | 4
+46 | | 4
+19 | | 5
+108 | | 3
+9 | 305 | 6
+91 | 211 | 5
+41 | 302 | 5
+106 | 206 | 5
+123 | | 4
+16 | | 6
+126 | | 5
+97 | | 3
+20 | | 4
+15 | | 4
+79 | | 3
+40 | | 3
+9 | | 3
+26 | | 3
+96 | | 6
+35 | | 5
+38 | | 5
+96 | | 5
+12 | | 3
+63 | | 5
+66 | | 3
+44 | | 4
+129 | | 4
+55 | | 4
+93 | | 4
+98 | | 6
+(35 rows)
+
+3.  List all customers from cities that begin with the letter 'M'.
+
+cyf_hotels=# select \* from customers where city like 'M%';
+id | name | email | phone | address | city | postcode | country  
+-----+---------------------+------------------------------+--------------------+--------------------------------------------+-------------+----------+-------------
+3 | Alice Evans | alice.evans001@hotmail.com | 0161 345 6789 | 3 High Road | Manchester | m13 4ef | UK
+4 | Mohammed Trungpa | mo.trungpa@hotmail.com | 0161 456 7890 | 25 Blue Road | Manchester | M25 6GH | UK
+6 | Nadia Sethuraman | nadia.sethuraman@mail.com | | 135 Green Street | Manchester | M10 4BG | UK
+8 | Martín Sommer | martin.sommer@dfgg.net | (91) 555 22 82 | C/ Romero, 33 | Madrid | 28016 | Spain
+9 | Laurence Lebihan | laurence.lebihan@xmzx.net | 91.24.4555 | 12, rue des Bouchers | Marseille | 13008 | France
+14 | Peter Ferguson | peter.ferguson@mxnx.net | 03 9520 4555 | 636 St Kilda Road, Level 3 | Melbourne | 3004 | Australia
+22 | Diego Freyre | diego.freyre@amyr.net | (91) 555 94 44 | C/ Moralzarzal, 86 | Madrid | 28034 | Spain
+41 | Rachel Ashworth | rachel.ashworth@rzyb.net | (171) 555-1555 | Fauntleroy Circus | Manchester | EC2 5NT | UK
+55 | Jean Fresnière | jean.fresnière@uxsm.net | (514) 555-8054 | 43 rue St. Laurent | Montréal | H1J 1C3 | Canada
+56 | Alejandra Camino | alejandra.camino@omet.net | (91) 745 6555 | Gran Vía, 1 | Madrid | 28001 | Spain
+66 | Peter Franken | peter.franken@fszx.net | 089-0877555 | Berliner Platz 43 | München | 80805 | Germany
+88 | Jesus Fernandez | jesus.fernandez@cgxs.net | +34 913 728 555 | Merchants House, 27-30 Merchant's Quay | Madrid | 28023 | Spain
+91 | Laurence Lebihan | laurence.lebihan@xmzx.net | 91.24.4555 | 12, rue des Bouchers | Marseille | 13008 | France
+95 | Karin Josephs | karin.josephs@gyfv.net | 0251-555259 | Luisenstr. 48 | Münster | 44087 | Germany
+103 | Arnold Cruz | arnold.cruz@awqa.net | +63 2 555 3587 | 15 McCallum Street, NatWest Center #13-03 | Makati City | 1227 MM | Philippines
+105 | Akiko Shimamura | akiko.shimamura@pipl.net | +81 3 3584 0555 | 2-2-8 Roppongi | Minato-ku | 106-0032 | Japan
+109 | Michael Donnermeyer | michael.donnermeyer@lvpk.net | +49 89 61 08 9555 | Hansastr. 15 | Munich | 80686 | Germany
+118 | Martín Sommer | martín.sommer@wcoa.net | (91) 555 22 82 | C/ Araquil, 67 | Madrid | 28023 | Spain
+121 | Carmen Anton | carmen.anton@bhmy.net | +34 913 728555 | c/ Gobelas, 19-1 Urb. La Florida | Madrid | 28023 | Spain
+123 | Franco Ricotti | franco.ricotti@ycbk.net | +39 022515555 | 20093 Cologno Monzese, Alessandro Volta 16 | Milan | | Italy
+125 | Hanna Moos | hanna.moos@fmga.net | 0621-08555 | Forsterstr. 57 | Mannheim | 68306 | Germany
+(21 rows)
+
+4.  Make a new room type of PENTHOUSE with a default rate of £185.00
+
+cyf_hotels=# select \* from room_types;
+room_type | def_rate
+--------------+----------
+FAMILY | 123.00
+PREMIER | 110.00
+PREMIER PLUS | 123.00
+PREMIUM | 85.00
+PREMIUM PLUS | 98.00
+PENTHOUSE | 185.00
+(6 rows)
+
+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).
+
+cyf_hotels=# insert into rooms (room_no, rate, room_type) values (501, 185.00, 'PENTHOUSE'), (502, 185.00, 'PENTHOUSE');
+INSERT 0 2
+cyf_hotels=# select \* from rooms;
+room_no | rate | room_type | no_guests
+---------+--------+--------------+-----------
+101 | 85.00 | PREMIUM | 2
+102 | 85.00 | PREMIUM | 2
+103 | 85.00 | PREMIUM | 2
+104 | 85.00 | PREMIUM | 2
+105 | 85.00 | PREMIUM | 2
+106 | 85.00 | PREMIUM | 2
+107 | 85.00 | PREMIUM | 2
+108 | 98.00 | PREMIUM PLUS | 2
+109 | 98.00 | PREMIUM PLUS | 2
+110 | 98.00 | PREMIUM PLUS | 2
+111 | 98.00 | PREMIUM PLUS | 2
+112 | 98.00 | PREMIUM PLUS | 2
+201 | 85.00 | PREMIUM | 2
+202 | 85.00 | PREMIUM | 2
+203 | 85.00 | PREMIUM | 2
+204 | 85.00 | PREMIUM | 2
+205 | 85.00 | PREMIUM | 3
+206 | 85.00 | PREMIUM | 3
+207 | 85.00 | PREMIUM | 3
+208 | 98.00 | PREMIUM PLUS | 2
+209 | 98.00 | PREMIUM PLUS | 2
+210 | 98.00 | PREMIUM PLUS | 2
+211 | 98.00 | PREMIUM PLUS | 3
+212 | 98.00 | PREMIUM PLUS | 3
+301 | 110.00 | PREMIER | 2
+302 | 110.00 | PREMIER | 2
+303 | 110.00 | PREMIER | 2
+304 | 110.00 | PREMIER | 2
+305 | 110.00 | PREMIER | 2
+306 | 110.00 | PREMIER | 2
+307 | 110.00 | PREMIER | 2
+308 | 123.00 | PREMIER PLUS | 2
+309 | 123.00 | PREMIER PLUS | 2
+310 | 123.00 | PREMIER PLUS | 2
+311 | 123.00 | PREMIER PLUS | 2
+312 | 123.00 | PREMIER PLUS | 2
+401 | 110.00 | PREMIER | 2
+402 | 110.00 | PREMIER | 2
+403 | 110.00 | PREMIER | 2
+404 | 110.00 | PREMIER | 2
+405 | 110.00 | PREMIER | 2
+406 | 110.00 | PREMIER | 2
+407 | 110.00 | PREMIER | 2
+408 | 123.00 | PREMIER PLUS | 2
+409 | 123.00 | PREMIER PLUS | 2
+410 | 123.00 | PREMIER PLUS | 2
+411 | 123.00 | FAMILY | 4
+412 | 123.00 | FAMILY | 4
+501 | 185.00 | PENTHOUSE |  
+ 502 | 185.00 | PENTHOUSE |  
+(50 rows)
+
+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.
+
+        412 | 123.00 | FAMILY       |         4
+         501 | 185.00 | PENTHOUSE    |
+         502 | 185.00 | PENTHOUSE    |
+         503 | 143.00 | PREMIER PLUS |
+
+    (51 rows)
+
+7.  The hotel manager wishes to know how many rooms were occupied any time during the previous month - find that information.
+
+cyf_hotels=# select count (id) from reservations where checkin_date between '2023-07-01' and '2023-07-31';
+count
+
+---
+
+    41
+
+(1 row)
+
+8.  Get the total number of nights that customers stayed in rooms on the second floor (rooms 201 - 299).
+
+cyf_hotels=# select floor, sum(nights) as total_nights from (select trunc(room_no/100) as floor, (checkout_date - checkin_date) as nights from reservations where trunc(room_no/100)=2 ) subquery group by floor;
+floor | total_nights
+-------+--------------
+2 | 63
+(1 row)
+
+9.  How many invoices are for more than £300.00 and what is their grand total and average amount?
+
+cyf_hotels=# select count(\*) as invoices, sum(total) as grand_total, avg(total) as average_amount from invoices where total >= 300;
+invoices | grand_total | average_amount  
+----------+-------------+----------------------
+25 | 12928.00 | 517.1200000000000000
+(1 row)
+
+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**)