The Art of SQL Server FILESTREAM - Red Gate Software

Chapter 7: FILESTREAM Database AdministrationRun the code in Listing 7-8 to update the FILESTREAM columns. The first column isupdated to NULL and SQL Server discards the FILESTREAM data file associated withthe field. The second column is updated with a new value, and SQL Server creates a newversion of the file containing the new value, and discards the previous file.UPDATE ItemsSET ItemImage1 = NULL ,ItemImage2 = 0x2Listing 7-8:Updating the columns to create garbage files.After the UPDATE operation, you will see three files in the FILESTREAM data container.Out of the three, two are no longer needed. Those two files will be registered in theFILESTREAM tombstone table. We can try to read the names of those files from thattable, but first we need to find out its name, as shown in Listing 7-9.SELECTnameFROM sys.internal_tablesWHERE name LIKE 'FILESTREAM_tomb%'/*name--------------------------------FILESTREAM_tombstone_2073058421*/Listing 7-9:Retrieving the name of the FILESTREAM tombstone table.However, the tombstone table cannot be accessed from the user mode queries. Toread information from this table, we need to connect to the server using DedicatedAdministrator Connection (DAC).282