> Do a query, get back a handle to a file that you can treat just like you opened it yourself Things are a bit more complex. For one, the trivial problem of cl

> Do a query, get back a handle to a file that you can treat just like you opened it yourself Things are a bit more complex. For one, the trivial problem of client vs. server host. The DB cannot return a handle (a FD) from the server, because it has no meaning on the host running the app. The second problem is that any file manipulation must conform to the DB semantics for transactions, locking, rollback and recovery. What you describe does exists, is the FileStream feature that dates back to 2007 if I remember correctly. I'm describing the SQL Server feature since this is what I'm familiar with. The app queries the DB for a token, using GET_FILESTREAM_TRANSACTION_CONTEXT[0] and then uses this token to get a Win32 handle for the 'file' using OpenSqlFilestream[1]. The result handle is valid for usual file handle operations (read, write, seek etc). There were great expectations on this feature, but in real life it flopped. For one it caused all sort of operational headache from the increased DB files size (increased backups size etc) or from problems like having to investigate 'filestream thumbstone status'[2]. But more importantly, adoption required application rewrite (to use the OpenSqlFilestream), which of course never materialized. File Tables is a newer stab at this problem and this one does allow to expose the DB files as a network share and apps can create and manipulate files on this share and everything is backed by the DB behind the scenes. But turns out a lot of apps do all sort of crazy things with the files, like copy-rename and swap as means to do failure safe saves, but many such operations are significantly more expensive in DB context. And when the DB content is manipulated directly by the apps that 'think' they interact with the filesystem, a lot of useful metadata is never collected in the DB, since the file API used never requires it (think file author, subject etc). [0] https://docs.microsoft.com/en-us/sql/t-sql/functions/get-filestream-transaction-context-transact-sql https://docs.microsoft.com/en-us/sql/t-sql/functions/get-fil... [1] https://docs.microsoft.com/en-us/sql/relational-databases/blob/access-filestream-data-with-opensqlfilestream https://docs.microsoft.com/en-us/sql/relational-databases/bl... [2] https://www.sqlskills.com/blogs/paul/filestream-garbage-collection/ https://www.sqlskills.com/blogs/paul/filestream-garbage-coll...