diff --git a/CombineTwoTables.sql b/CombineTwoTables.sql
new file mode 100644
index 0000000..d8ea450
--- /dev/null
+++ b/CombineTwoTables.sql
@@ -0,0 +1 @@
+Select p.firstName,p.lastName,a.city,a.state from Person p Left join Address a on a.personId=p.personId;
\ No newline at end of file
diff --git a/CusStrictlyIncrease.sql b/CusStrictlyIncrease.sql
new file mode 100644
index 0000000..281d619
--- /dev/null
+++ b/CusStrictlyIncrease.sql
@@ -0,0 +1,16 @@
+WITH CTE AS (
+    SELECT 
+        customer_id, 
+        YEAR(order_date) AS year, 
+        SUM(price) AS price 
+    FROM orders 
+    GROUP BY customer_id, year
+)
+SELECT c1.customer_id 
+FROM CTE c1 
+LEFT JOIN CTE c2 
+ON c1.customer_id = c2.customer_id 
+   AND c1.year + 1 = c2.year 
+   AND c1.price < c2.price 
+GROUP BY c1.customer_id 
+HAVING COUNT(c2.customer_id) = COUNT(c1.customer_id);
diff --git a/GamePlayAnalysis2.sql b/GamePlayAnalysis2.sql
new file mode 100644
index 0000000..160f393
--- /dev/null
+++ b/GamePlayAnalysis2.sql
@@ -0,0 +1,12 @@
+#Approach 1:
+Select a.player_id, a.device_id as first_login from Activity a where a.event_date in (select min(b.event_date) From Activity b where a.player_id=b.player_id);
+
+
+#Approach 2:
+select player_id,first_value(device_id) over (partition by player_id order by event_date) as device_id from activity;
+
+
+
+#Approach 3:
+select player_id,last_value(device_id) over (partition by player_id order by event_date desc range between unbounded preceding and unbounded following) as device_id from activity;
+
diff --git a/GamePlayAnalysis3.sql b/GamePlayAnalysis3.sql
new file mode 100644
index 0000000..7e87363
--- /dev/null
+++ b/GamePlayAnalysis3.sql
@@ -0,0 +1 @@
+select player_Id, event_date, sum(games_played) over (partition by player_id order by event_date) as games_played_so_far from activity;
\ No newline at end of file
diff --git a/ShortestDis.sql b/ShortestDis.sql
new file mode 100644
index 0000000..c91712d
--- /dev/null
+++ b/ShortestDis.sql
@@ -0,0 +1,18 @@
+#Approach 1:
+Select round(sqrt(min(pow(p2.x-p1.x,2)+pow(p2.y-p1.y,2))),2) as ‘shortest’ from point2d p1 inner join point2d p2 on (p1.x>=p2.x and p1.y>p2.y) or (p1.x<=p2.x and p1.y>p2.y) or (p1.x<p2.x and p1.y=p2.y);
+
+
+
+#Approach 2:
+WITH RankedDistances AS (
+    SELECT 
+        p1.x AS x1, p1.y AS y1, p2.x AS x2, p2.y AS y2,
+        SQRT(POW(p2.x - p1.x, 2) + POW(p2.y - p1.y, 2)) AS distance,
+        RANK() OVER (ORDER BY SQRT(POW(p2.x - p1.x, 2) + POW(p2.y - p1.y, 2))) AS rank
+    FROM Point2D p1
+    INNER JOIN Point2D p2
+    ON (p1.x != p2.x OR p1.y != p2.y)
+)
+SELECT ROUND(distance, 2) AS 'shortest'
+FROM RankedDistances
+WHERE rank = 1;