From be53f0e6fff71536079eb00a536116360cae44ea Mon Sep 17 00:00:00 2001
From: tejas274 <shahtejas274@gmail.com>
Date: Fri, 23 May 2025 09:15:28 -0400
Subject: [PATCH 1/4] feat: problem 1 added

---
 problem1-180-consecutive-numbers.sql | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 problem1-180-consecutive-numbers.sql

diff --git a/problem1-180-consecutive-numbers.sql b/problem1-180-consecutive-numbers.sql
new file mode 100644
index 0000000..0bfa358
--- /dev/null
+++ b/problem1-180-consecutive-numbers.sql
@@ -0,0 +1,17 @@
+select
+    distinct log1.num as ConsecutiveNums
+from
+    Logs log1,Logs log2,Logs log3
+where log1.id = log2.id - 1
+and log2.id = log3.id -1
+and log1.num =log2.num
+and log2.num =log3.num
+
+
+-- join
+SELECT DISTINCT log1.num as ConsecutiveNums
+FROM Logs log1
+JOIN Logs log2 ON log1.id = log2.id - 1
+JOIN Logs log3 ON log2.id = log3.id - 1
+WHERE log1.num = log2.num
+  AND log2.num = log3.num
\ No newline at end of file

From bd25a72ad0def3981d09a71d863b96f3624bfb7e Mon Sep 17 00:00:00 2001
From: tejas274 <shahtejas274@gmail.com>
Date: Fri, 23 May 2025 09:23:27 -0400
Subject: [PATCH 2/4] feat: problem 1 added

---
 problem1-180-consecutive-numbers.sql | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/problem1-180-consecutive-numbers.sql b/problem1-180-consecutive-numbers.sql
index 0bfa358..4c53d66 100644
--- a/problem1-180-consecutive-numbers.sql
+++ b/problem1-180-consecutive-numbers.sql
@@ -14,4 +14,22 @@ FROM Logs log1
 JOIN Logs log2 ON log1.id = log2.id - 1
 JOIN Logs log3 ON log2.id = log3.id - 1
 WHERE log1.num = log2.num
-  AND log2.num = log3.num
\ No newline at end of file
+  AND log2.num = log3.num
+
+
+--window function
+WITH ThreeConsecutive AS (
+  SELECT
+    CASE
+      WHEN num = LAG(num, 1) OVER (ORDER BY id)
+        AND num = LAG(num, 2) OVER (ORDER BY id)
+      THEN num
+    END AS ConsecutiveNums
+  FROM Logs
+)
+
+SELECT
+    DISTINCT ConsecutiveNums
+FROM ThreeConsecutive
+WHERE
+    ConsecutiveNums IS NOT NULL;
\ No newline at end of file

From f6e7e80c2c6f06b23d267360a0348eb9299bc746 Mon Sep 17 00:00:00 2001
From: tejas274 <shahtejas274@gmail.com>
Date: Sun, 25 May 2025 09:16:32 -0400
Subject: [PATCH 3/4] problem 2 and problem 3 added

---
 problem2-2142-number-of-passanger-bus.sql | 25 +++++++++++++++++++++++
 problem3-1141-user-activity-30days.sql    |  8 ++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 problem2-2142-number-of-passanger-bus.sql
 create mode 100644 problem3-1141-user-activity-30days.sql

diff --git a/problem2-2142-number-of-passanger-bus.sql b/problem2-2142-number-of-passanger-bus.sql
new file mode 100644
index 0000000..5993247
--- /dev/null
+++ b/problem2-2142-number-of-passanger-bus.sql
@@ -0,0 +1,25 @@
+WITH bus_time_passenger AS (
+    SELECT
+        p.passenger_id,
+        MIN(b.arrival_time) AS bus_time
+    FROM
+        Passengers p
+    LEFT JOIN
+        Buses b
+        ON p.arrival_time <= b.arrival_time
+    GROUP BY
+        p.passenger_id
+)
+
+SELECT
+    b.bus_id,
+    COUNT(bp.bus_time) AS passengers_cnt
+FROM
+    Buses b
+LEFT JOIN
+    bus_time_passenger bp
+    ON bp.bus_time = b.arrival_time
+GROUP BY
+    b.bus_id
+ORDER BY
+    b.bus_id;
\ No newline at end of file
diff --git a/problem3-1141-user-activity-30days.sql b/problem3-1141-user-activity-30days.sql
new file mode 100644
index 0000000..027d9cb
--- /dev/null
+++ b/problem3-1141-user-activity-30days.sql
@@ -0,0 +1,8 @@
+select
+activity_date as day,
+count(distinct user_id) as active_users
+from Activity
+where activity_date >  DATE_SUB('2019-07-27', INTERVAL 30 DAY)
+and activity_date <= '2019-07-27'
+group by activity_date
+order by activity_date
\ No newline at end of file

From fb07f8d8dee93d44c7d6641880823110f12f70aa Mon Sep 17 00:00:00 2001
From: tejas274 <shahtejas274@gmail.com>
Date: Thu, 5 Jun 2025 11:29:04 -0400
Subject: [PATCH 4/4] problem 4 added

---
 problem4-2252-dynemic-pivot-table.sql | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 problem4-2252-dynemic-pivot-table.sql

diff --git a/problem4-2252-dynemic-pivot-table.sql b/problem4-2252-dynemic-pivot-table.sql
new file mode 100644
index 0000000..81c777d
--- /dev/null
+++ b/problem4-2252-dynemic-pivot-table.sql
@@ -0,0 +1,19 @@
+CREATE PROCEDURE PivotProducts()
+BEGIN
+
+    SET SESSION GROUP_CONCAT_MAX_LEN = 10000000;
+    SET @cols = (
+    SELECT 
+        GROUP_CONCAT( DISTINCT   
+        CONCAT('MAX(IF(store = ''',store,''', price, NULL)) AS ', store) 
+        )
+    FROM Products order by store);
+
+    SET @query = CONCAT('SELECT product_id, ', @cols, ' FROM Products GROUP BY product_id ;');
+
+
+    PREPARE stmt FROM @query;
+    EXECUTE stmt;
+
+
+END
\ No newline at end of file