Medical imaging data is typically dense 3D grids of density samples. A relational database could hold a pointer to the file, but not the 5GB-500GB dataset files

Medical imaging data is typically dense 3D grids of density samples. A relational database could hold a pointer to the file, but not the 5GB-500GB dataset files. One dataset is typically a folder of various files, metadata, and other information representing an entire filesystem. Back in the day, the datasets would be RAID across several machines. Now they're virtual filesystems. The database could manage this info, but not hold the actual dataset itself. I imagine this is what the commentter means. The DBA probably said "it all needs to be in the database", and that just doesn't make sense.