Completed SQL3

Consecutive Numbers.sql

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+# Write your MySQL query statement below
+WITH CTE AS (SELECT *, LEAD(num, 1) OVER() AS next_1, LEAD(num, 2) OVER() AS next_2
+FROM logs)
+SELECT DISTINCT num AS ConsecutiveNums
+FROM CTE
+WHERE num = next_1
+AND num = next_2;

Dynamic Pivoting of a Table.sql

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+CREATE PROCEDURE PivotProducts()
+BEGIN
+	# Write your MySQL query statement below.
+    SET SESSION GROUP_CONCAT_MAX_LEN = 1000000;
+    SET @sql = null;
+    SELECT GROUP_CONCAT(DISTINCT CONCAT('SUM(IF(store = "',store,'", price,null))', store))INTO @sql 
+    FROM Products;
+    SET @sql=CONCAT('SELECT product_id, ', @sql, ' FROM Products GROUP BY 1');
+    PREPARE STATEMENT FROM @sql;
+    EXECUTE STATEMENT;
+    DEALLOCATE PREPARE STATEMENT;
+END

Number of Passengers in Each Bus.sql

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+# Write your MySQL query statement below
+WITH CTE AS (
+    SELECT p.passenger_id, min(b.arrival_time) AS arrival_time FROM Passengers p 
+    INNER JOIN Buses b 
+    ON p.arrival_time <= b.arrival_time
+    GROUP BY p.passenger_id
+)
+
+SELECT b.bus_id, COUNT(CTE.arrival_time) AS passengers_CNT 
+FROM Buses b 
+LEFT JOIN CTE
+ON b.arrival_time = CTE.arrival_time
+GROUP BY b.bus_id
+ORDER BY b.bus_id;

User Activity.sql

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+# Write your MySQL query statement below
+SELECT activity_date AS day, COUNT(DISTINCT user_id) AS active_users
+FROM activity
+WHERE activity_date > '2019-06-27' AND activity_date <= '2019-07-27'
+GROUP BY activity_date;