gst

src/data/courses/sql-mastery/chapters/multi-table-queries/lessons/high-value-orders.md

@@ -39,7 +39,7 @@ setup: |
   ```
 ---
 
-The bookstore wants to identify the highest value orders i.e. the orders worth more than or equal to $500. Write a query to find order amounts, dates along with the customer names and emails.
+The bookstore wants to identify the highest value orders i.e. the orders worth more than or equal to $500. Write a query to find order amounts, dates along with the customer names.
 
 We have the `customer` and `sale` tables.
 
@@ -69,7 +69,6 @@ We have the `customer` and `sale` tables.
 Write a query to find the orders above $500 along with the information of the customers. Your output should have the following columns:
 
 - `customer_name`
-- `customer_email`
 - `order_amount`
 - `order_date`
 
@@ -77,17 +76,16 @@ The output should be ordered by the `order_amount` in descending order.
 
 ## Expected Output
 
-| customer_name | customer_email         | order_amount | order_date        |
-| ------------- | ---------------------- | ------------ | ----------------- |
-| Jane Smith    | jane.smith@example.com | 600.00       | November 11, 2024 |
-| John Doe      | john.doe@example.com   | 550.00       | October 20, 2024  |
+| customer_name | order_amount | order_date        |
+| ------------- | ------------ | ----------------- |
+| Jane Smith    | 600.00       | November 11, 2024 |
+| John Doe      | 550.00       | October 20, 2024  |
 
 ## Solution
 
 ```sql
 SELECT
     c.name,
-    c.email,
     s.total_amount,
     TO_CHAR(s.order_date, 'Month DD, YYYY') AS order_date
 FROM customer c

src/data/courses/sql-mastery/chapters/multi-table-queries/lessons/recent-orders.md

@@ -0,0 +1,97 @@
+---
+title: Recent 3 Orders
+description: Practice using LIMIT to get the top N records
+order: 110
+type: challenge
+setup: |
+  ```sql
+  CREATE TABLE customer (
+      id INT PRIMARY KEY,
+      name VARCHAR(255),
+      email VARCHAR(255)
+  );
+
+  CREATE TABLE sale (
+      id INT PRIMARY KEY,
+      customer_id INT,
+      order_date DATE,
+      total_amount DECIMAL(10,2)
+  );
+
+  INSERT INTO customer (id, name, email)
+  VALUES 
+      (1, 'John Doe', 'john.doe@example.com'),
+      (2, 'Jane Smith', 'jane.smith@example.com'),
+      (3, 'Alice Johnson', 'alice.johnson@example.com'),
+      (4, 'Bob Brown', 'bob.brown@example.com'),
+      (5, 'Charlie Davis', 'charlie.davis@example.com'),
+      (6, 'David Lee', 'david.lee@example.com');
+
+  INSERT INTO sale (id, customer_id, order_date, total_amount)
+  VALUES 
+      (1, 1, '2024-12-02', 100.00),
+      (2, 1, '2024-11-15', 150.00),
+      (3, 1, '2024-10-20', 550.00),
+      (4, 4, '2024-12-26', 250.00),
+      (5, 5, '2024-11-12', 300.00),
+      (6, 2, '2024-11-23', 300.00),
+      (7, 2, '2024-11-11', 600.00);
+  ```
+---
+
+The bookstore wants to display the 3 most recent orders placed by customers. Write a query to retrieve the customer names, order dates, and total amounts of these orders, ordered by the most recent first.
+
+We have the `customer` and `sale` tables.
+
+> `customer` table has the list of customers.
+
+| id  | name          | email                     |
+| --- | ------------- | ------------------------- |
+| 1   | John Doe      | john.doe@example.com      |
+| 2   | Jane Smith    | jane.smith@example.com    |
+| 3   | Alice Johnson | alice.johnson@example.com |
+| 4   | Bob Brown     | bob.brown@example.com     |
+| 5   | Charlie Davis | charlie.davis@example.com |
+| 6   | David Lee     | david.lee@example.com     |
+
+> `sale` table has the list of sales.
+
+| id  | customer_id | order_date | total_amount |
+| --- | ----------- | ---------- | ------------ |
+| 1   | 1           | 2024-12-02 | 100.00       |
+| 2   | 1           | 2024-11-15 | 150.00       |
+| 3   | 1           | 2024-10-20 | 200.00       |
+| 4   | 4           | 2024-12-26 | 250.00       |
+| 5   | 5           | 2024-11-12 | 300.00       |
+| 6   | 2           | 2024-11-23 | 300.00       |
+| 7   | 2           | 2024-11-11 | 300.00       |
+
+Write a query to find the 3 most recent orders along with the information of the customers. Your output should have the following columns:
+
+- `customer_name`
+- `order_date`
+- `order_amount`
+
+The output should be ordered by the `order_date` in descending order.
+
+## Expected Output
+
+| customer_name | order_date     | total_amount |
+| ------------- | -------------- | ------------ |
+| Bob Brown     | December, 2024 | 250.00       |
+| John Doe      | December, 2024 | 100.00       |
+| Jane Smith    | November, 2024 | 300.00       |
+
+## Solution
+
+```sql
+SELECT
+    c.name,
+    TO_CHAR(s.order_date, 'Month, YYYY') AS order_date,
+    s.total_amount
+FROM customer c
+JOIN sale s
+    ON c.id = s.customer_id
+ORDER BY s.order_date DESC
+LIMIT 3;
+```