Laravel orderBy slowing down response greatly - mysql

Question

Leaving out unnecessary information the table structure is as follows(not listing all the with relations):
products
id
launch_date
name
product_view_history
id
account_id
product_id
timestamps
I have query that is taking and irregularly long amount of time. With all the profiling I've done, the actual time spent in SQL is very small(<50 ms) but the time this code takes to execute is in the 900+ms range:
$this->select('products.*', DB::raw('COUNT(product_view_history.id) as view_count'))
->leftJoin('product_view_history', 'product_view_history.product_id', '=', 'products.id', 'outer')
->groupBy('product_view_history.product_id')
->orderBy('view_count', 'DESC')
->orderBy('products.id', 'DESC')
->whereNotNull('products.launch_date')
->with(['owner.images', 'owner.star', 'owner.follows', 'owner.followers', 'company.products.alphas'])
->take(Config::get('xxxx.limits.small'))
->get();
However the time it takes for this code to execute is reduced the the appropriate <50ms if I comment out ->orderBy('view_count', 'DESC'). If I swap out get() with toSql() and run both those queries manually I'm finding the times to be relatively similar and small. To be clear to measure the time this is taking is not SQL query time; I am just getting the time in milliseconds before and directly after this is done and logging the difference.
Can anyone see any reason why ->orderBy('view_count', 'DESC') would add close to a full second of time to the execution of code, even though the SQL itself is not/minimally slower?

Answer 1

It seems like executing the query raw and hydrating and loading seem to speed up the query. This does not answer WHY that order by would cause such an issue but it does answer how to get around the issue at hand:
$products = self::hydrate(DB::select(
"select `products`.*, COUNT(product_view_history.id) as view_count
from `products` left join `product_view_history`
on `product_view_history`.`product_id` = `products`.`id`
where `products`.`launch_date` is not null
group by `product_view_history`.`product_id`
order by `view_count` desc, `products`.`id` desc limit {$limit}"))
->load(['owner.images', 'owner.star', 'owner.follows', 'owner.followers', 'company.products.alphas']);

Answer 2

For me it was caused by using "wrong" data types in the where query.
For example I filtered by a column called "username" which is a varchar but inserted an Int as value to filter by.
It took very long when using orderBy but when removing the orderBy it was fast again.
The solution was at least for me to cast the username to String and the orderBy was fluent as before. I do not know the real reason but maybe Eloquent casts or sorts differently when using not matching data types.