MySQL query performance guide with subquery in WHERE clause using Laravel 9
I'm stuck trying to I've searched everywhere and can't find a clear answer. I'm stuck on something that should probably be simple. I've searched everywhere and can't find a clear answer. I'm having trouble with I'm experiencing important performance optimization with a MySQL query that utilizes a subquery in the WHERE clause while using Laravel 9. The specific query looks like this: ```php $results = DB::table('orders') ->whereIn('customer_id', function($query) { $query->select('id') ->from('customers') ->where('status', 'active'); }) ->get(); ``` When I run this query on a dataset of about 1 million records, it takes a few seconds to return the results, which is not ideal for user experience. I've tried adding indexes to both the `customer_id` column in the `orders` table and the `id` column in the `customers` table, but I haven't seen much improvement. I also experimented with breaking the query into two separate queries, retrieving the active customer IDs first and then querying the orders, which seemed to improve performance slightly but still not to the level I expected. The raw SQL generated by Laravel for this query is: ```sql SELECT * FROM orders WHERE customer_id IN (SELECT id FROM customers WHERE status = 'active'); ``` The expected outcome was that this would be reasonably fast, given the proper indexing. However, I'm getting an `SQLSTATE[HY000]: General behavior: 2006 MySQL server has gone away` behavior intermittently, indicating that the server might be timing out when the query is too complex. Any suggestions on optimizing this query or alternative approaches I might consider? Are there any best practices I could follow in this context to avoid performance optimization? I'm using MySQL version 8.0.26, and the application runs on a shared hosting environment. Thanks in advance for any insights! Am I approaching this the right way? I recently upgraded to Php LTS. What am I doing wrong? I'm working in a Debian environment. What am I doing wrong? This is part of a larger application I'm building. Any help would be greatly appreciated! This issue appeared after updating to Php latest. Could someone point me to the right documentation?