The Art of SQL Server FILESTREAM - Red Gate Software

Chapter 11: FileTableWe may also need to create a new file in a subfolder. We must ensure that we createthis new file in a valid hierarchy, which means that we must include the folder'spath_locator in the path_locator of this new record. As an example, Listing 11-19shows a simplified view of the structure we just created using Listing 11-17 andListing 11-18.SELECT CAST(path_locator AS VARCHAR(4000)), name,path_locator.GetLevel() AS 'level', is_directoryFROM Documents/*path_locator name level is_directory------------ ----------- ----- ------------/1.1.1/ ReadMe.txt 1 0/2.2.2/ Order Files 1 1*/Listing 11-19: Querying the contents of the Documents table.While the path_locator values you will find are more complex, the point is toillustrate that the file and the folder have a different hierarchyid (path_locator)value, but that the level in the hierarchy is both 1. The new file we want to add shouldhave a path_locator and level value like the ones shown in Table 11-2.path_locator name level/2.2.2/3.3.3/ NewFile.txt 2Table 11-2:path_locator value for the new file.We must create the new file record as a child of the Order Files folder, so we cannotuse the DEFAULT constraint on the path_locator column to let SQL Server create apath_locator value located in the FileTable root. Instead, we must first find the parentfolder's path_locator value and construct a new path_locator value that is a childvalue of the parent folder's path_locator. Listing 11-20 shows how this can be done.416