Changes between Version 16 and Version 17 of AdvancedApplicationDevelopment

Timestamp:

09/30/25 09:01:47 (2 weeks ago)

Author:

223270

Comment:

--

AdvancedApplicationDevelopment

@@ -242 +242 @@
 
 === Релациска алгебра
-{{{
-SELECT d.location_name, AVG(r.quality) AS avg_rating 
+Најпопуларни дестинации по просечна оцена и број на резервации
+{{{
+SELECT d.location_name, AVG(r.quality) AS avg_rating, COUNT(res.id_reservation) AS total_res 
 FROM destination d 
 JOIN review r ON d.id_destination = r.id_destination 
+JOIN reservation res ON d.id_destination = res.id_destination 
 GROUP BY d.location_name 
-HAVING AVG(r.quality) > 4;
-
-
-π_{d.location_name, avg_rating} (
-γ_{d.location_name; avg_rating ← AVG(r.quality)} (
-destination ⨝{d.id_destination = r.id_destination} review
+HAVING AVG(r.quality) > 4 AND COUNT(res.id_reservation) > 20;
+
+
+π_{d.location_name, avg_rating, total_res} (
+γ_{d.location_name; avg_rating ← AVG(r.quality), total_res ← COUNT(res.id_reservation)} (
+(destination ⨝ review ⨝ reservation)
 )
-σ{avg_rating > 4}
+σ{avg_rating > 4 ∧ total_res > 20}
 )
 }}}