[duped]

> JSON is there for human to read a record of data by group.

That's what tree is for

> I think it is only good to use directory as data table to store JSON data files, but not for JSON data properties.

I see that as no better than one big JSON file or a normal NoSQL database.

If you're really fancy then the whole DB is just a VFS and those JSON files aren't real files, just a serialized form of the DB.

[xyheme]

directory tree is not as easy to view and edit as JSON.

One big JSON file is harder.

I am not fancy, and the aim is to simply use file system as database.

Not fancy stuff like "database as file system as database".

[duped]

> directory tree is not as easy to view and edit as JSON.

    tree path/to
    cat path/to/key
    echo "1" > path/to/key

But my point is that you're not using the file system as a database. You're using it as an index, and haven't considered about multiple readers/writers to those individual JSON files that are doing the real work as databases. It's kind of like writing JSON into a SQL table. You can do it, but probably not to store important data within that JSON that always needs to be queried and ser/deserialized for any kind of read or write. If you need that, you probably want NoSQL.