diff --git a/mock.sql b/mock.sql
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+-- Question: https://leetcode.com/problems/top-travellers/description/
+
+-- # Write your MySQL query statement below
+-- with cte as(
+-- select u.name as name ,sum(distance) as travelled_distance_one
+-- from users u
+-- left join rides r on u.id=r.user_id
+-- group by user_id
+-- order by sum(distance) desc,name asc)
+
+-- select name, ifnull(travelled_distance_one,0) as travelled_distance
+-- from cte;
+
+select name, ifnull(sum(distance),0) as travelled_distance
+from users u
+left join rides r on u.id=r.user_id
+group by user_id
+order by  travelled_distance desc,name asc;
+
+with cte as (
+select sale_date, fruit,sold_num,lead(sold_num) over(partition by sale_date order by fruit) as lea
+from sales)
+
+select sale_date,sold_num -lea as diff
+from cte
+where fruit='apples'
+order by sale_date;
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