Create article-views-ii.sql

kamyu104 · web-flow · commit 4cc3482dfdef · 2019-08-12T02:12:46.000+08:00
diff --git a/MySQL/article-views-ii.sql b/MySQL/article-views-ii.sql
@@ -0,0 +1,9 @@
+# Time:  O(nlogn)
+# Space: O(n)
+
+SELECT DISTINCT viewer_id AS id 
+FROM   views 
+GROUP  BY viewer_id, 
+          view_date 
+HAVING Count(DISTINCT article_id) > 1 
+ORDER  BY viewer_id
