Filenames are the keys, file data are the values, and there's metadata too, encapsulated in the directory data, inode data, etc. But the concept of a file is ju

Filenames are the keys, file data are the values, and there's metadata too, encapsulated in the directory data, inode data, etc. But the concept of a file is just a useful metaphor. A file is exactly identical to a directory or an executable, from the KV store's low level perspective. All the handling and interpretation happens up higher. I disagree that (most) files contain their own schema though. Sometimes the schema is incorporated by reference in the metadata, sometimes in the key name (filename). Some structured data formats contain a sort of self descriptive sub schema, but they always(?) require something higher up the chain to make sense of it. I can't think of any examples where that isn't the case, but I'll leave the question mark on the always because I'd like to be be proven wrong!