An application uses FSCTL_SQL_FILESTREAM_FETCH_OLD_CONTENT to make partial updates to FILESTREAM BLOB data. The DeviceIoControl function passes this value and the handle that is returned from OpenSqlFilestream to the FILESTREAM driver. The driver then forces a server-side copy of the current FILESTREAM data into the file that is referenced by the handle. If the application issues the FSCTL_SQL_FILESTREAM_FETCH_OLD_CONTENT value after the handle has been written to, the last write operation persists and previous write operations that were made to the handle are lost.
note
FILESTREAM relies on the SMB protocol for remote access.
