php - Laravel cache::put returns false for large objects when using DB driver

When I use Laravel's database cache driver and when I insert relatively small strings and objects cache::put works fine and returns true. However when I attempt to enter larger objects it returns false.

I can't seem to find what the limit is, where to configure it or how to debug issues with it?

I've tried changing the database schema to a large text in case the DB insert was failing and I've looked through the src/illuminate/cache folder for anything helpful but with no luck. I also can't see anything helpful in the Laravel cache documentation.

This is how I'm calling it

Cache::put('test-'.time(), $identities, now()->addDays(30)))

Solution:

I don't fully understand what's happening but it was something to do with the encoding.

var_dump(Cache::put('1', mb_substr('Javier Fern??ndez-L??pez', 0, 20, 'UTF-8'), now()->addDays(30)));

var_dump(Cache::put('2', 'Javier Fern??ndez-L??pez', now()->addDays(30)));

var_dump(Cache::put('3', substr('Javier Fern??ndez-L??pez', 0, 20), now()->addDays(30)));

The above returns

TRUE

TRUE

FALSE

Substr was returning something a part of the caching didn't like