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What is the equivalent of a directory, and of a file? From the relation point of view, what would your tables be? It doesn't map that well, the idea sounds int

by jasfi 5y ago

What is the equivalent of a directory, and of a file? From the relation point of view, what would your tables be? It doesn't map that well, the idea sounds intriguing, but in practice a filesystem seems like a better model for files.

dagss 5y ago
You would not have a "directory" in the sense you use the word (why would directory be required in a FILE system?) Instead a heap of files and you search for them using metadata (e.g. each file has an associated key value store that you search on). Music catalogues is a good example. In the 90s one vould wonder if the music sitting on HD should be organized as "Music/(genre)/(artist)" or "Music/(artist)/(genre)" as directories. Different choices was best for different persons. Eventually many music players for desktop (e.g. iTunes) just made a different metaphor. And Spotify, Netflix etc do not use a hierarchy but you search for items using metadata. Another example is e.g. /lib/libfoo-1.2.so Where one could instead have libraryname=foo scope=system version=1.2 sharedlibrary=true Or similar
- mnsc 5y ago
  > Music/(artist)/(genre) Well that's only necessary when your music library contains Zappa.
- jasfi 5y ago
  That's not relational, that's closer to a NoSQL store.
  - dagss 5y ago
    That is orthogonal, NoSQL can be used as a relational DB too. SQL is one way to do a relational DB. Also what I describe is close to SQL if e.g. you declare a set of properties and property types for each "filetype". Relational is one aspect of a DB. Schemaless or not is another aspect.
zozbot234 5y ago
A "file" is just a key-value entry where the "key" is some label in an arbitrary namespace, and the "value" is a blob of bytes. The "directories" of a relational FS would be dynamically generated: they would arise as query result sets based on user input, as opposed to being fixed and materialized on-disk. This is how the relational FS worked in BeOS, but the exact same "virtual directory" feature was also ported to some versions of Windows.

by jasfi 5y ago

dagss 5y ago

You would not have a "directory" in the sense you use the word (why would directory be required in a FILE system?) Instead a heap of files and you search for them using metadata (e.g. each file has an associated key value store that you search on). Music catalogues is a good example. In the 90s one vould wonder if the music sitting on HD should be organized as "Music/(genre)/(artist)" or "Music/(artist)/(genre)" as directories. Different choices was best for different persons. Eventually many music players for desktop (e.g. iTunes) just made a different metaphor. And Spotify, Netflix etc do not use a hierarchy but you search for items using metadata. Another example is e.g. /lib/libfoo-1.2.so Where one could instead have libraryname=foo scope=system version=1.2 sharedlibrary=true Or similar

mnsc 5y ago
> Music/(artist)/(genre) Well that's only necessary when your music library contains Zappa.
jasfi 5y ago
That's not relational, that's closer to a NoSQL store.
- dagss 5y ago
  That is orthogonal, NoSQL can be used as a relational DB too. SQL is one way to do a relational DB. Also what I describe is close to SQL if e.g. you declare a set of properties and property types for each "filetype". Relational is one aspect of a DB. Schemaless or not is another aspect.

zozbot234 5y ago

A "file" is just a key-value entry where the "key" is some label in an arbitrary namespace, and the "value" is a blob of bytes. The "directories" of a relational FS would be dynamically generated: they would arise as query result sets based on user input, as opposed to being fixed and materialized on-disk. This is how the relational FS worked in BeOS, but the exact same "virtual directory" feature was also ported to some versions of Windows.