The Art of SQL Server FILESTREAM - Red Gate Software

Chapter 11: FileTableCONVERT(VARCHAR(20), CONVERT(BIGINT, SUBSTRING(CONVERT(BINARY(16), NEWID()), 13, 4))) + '/'-- Insert a new record, specifying the new path_locatorINSERT INTO Documents (name, is_directory, path_locator)VALUES ('2013 Order Files', 1, @path_locator)Listing 11-22: Create a new subfolder using T-SQL.Some of the complexities in adding files and folders using T-SQL, specifically children ofother folders, may lead many developers to choose to use the Windows APIs instead. Thenext section discusses using the standard .NET System.File.IO namespace classes toachieve the same results.Using .NET file I/O APIsIn this section, we will use the traditional .NET file I/O APIs to access FileTable data.First, we will need to determine the path to the files and folders that are stored inthe FileTable. There is a new T-SQL function that allows us to get the UNC path of aFileTable's file_stream column: GetFileNamespacePath(). This function takestwo optional arguments; the first determines if a full path (which includes server name,share name and FileTable directory name) is returned or if a relative path is returned.The second argument determines the format in which the server name is returned, andis similar to the PathName() function found on a regular FILESTREAM column. (ThePathName() function works on the file_stream column, but returns the path youwould use to create a SqlFileStream instance in the context of a transaction.)Listing 11-23 shows an ADO.NET code snippet to retrieve the full path of a file whosename and location in the hierarchy is known. There are other ways to initially find thepath_locator of a file or folder, which can then be used to retrieve the UNC path.420