Create 01322-ads-performance.sql

Author: leetlab11

01322-ads-performance.sql

@@ -0,0 +1,12 @@
+-- my first intuition was to create 2 ctes- 1 with click count and 1 with (click + view) count using WHERE filter
+-- but this approach will not work because we cannot filter rows because we want all ad_ids, even those who were not clicked/viewed
+
+-- so we need to use case statement or the below approach
+
+select ad_id, 
+    ifnull(round((sum(action = 'Clicked'))/(sum(action = 'Clicked') + sum(action = 'Viewed'))*100, 2), 0) as ctr
+from Ads
+group by 1
+order by 2 desc, 1
+
+-- facebook- 1