MySQL query with JOIN returning incorrect results when using LEFT JOIN with aggregate functions in CodeIgniter 4
I'm sure I'm missing something obvious here, but I'm working with an scenario with a query that involves a LEFT JOIN along with aggregate functions, which is yielding incorrect results in my CodeIgniter 4 application. I have two tables: `orders` and `customers`. I want to count the total number of orders for each customer, even those who haven't placed any orders. However, the result set does not reflect the expected counts for customers with no orders. Here’s the query I'm currently using: ```sql SELECT c.id, c.name, COUNT(o.id) as total_orders FROM customers c LEFT JOIN orders o ON c.id = o.customer_id GROUP BY c.id, c.name; ``` In this case, I expect to see customers with zero orders showing up with a count of 0, but instead, I'm getting NULL values or incorrect counts. I have also tried using `IFNULL` to handle the NULLs, like this: ```sql SELECT c.id, c.name, IFNULL(COUNT(o.id), 0) as total_orders FROM customers c LEFT JOIN orders o ON c.id = o.customer_id GROUP BY c.id, c.name; ``` However, the output still shows unexpected results, especially when some customers are appearing with counts greater than expected. I’m using MySQL version 8.0.25 and CodeIgniter 4.1.5. What could be causing these discrepancies, and how can I ensure that I get the correct total orders for each customer? Any insights would be appreciated! How would you solve this?