100% reliable data storage is fundamentally impossible, but we can get pretty close with layers of protection against something going wrong at the physical level. Databases are typically agnostic to the specific protections that any given installation is using and mostly just assume that the data they read from disk is the data they wrote there previously. The protections might be in the filesystem itself but it’s more usual to push them down to the lower layers of RAID controllers and drive firmware. However it is impossible to truly guarantee protection against silent corruption and this happens often enough that many databases add their own mechanisms for detecting and correcting those rare cases where the data that they read isn’t the data that they previously wrote.