The Art of SQL Server FILESTREAM - Red Gate Software

Chapter 2: Getting Started with FILESTREAMAs such, the following steps are required, in case you want to convert an existingVARBINARY(MAX) column to FILESTREAM.1. Create a new VARBINARY(MAX) column with the FILESTREAM attribute.2. Copy the data from the VARBINARY(MAX) column to the FILESTREAM column usingan UPDATE statement. This will create a FILESTREAM file for each non-NULL valuebeing copied to the new column.3. Drop the original VARBINARY(MAX) column.4. Rename the new FILESTREAM column to the original name.The T-SQL script in Listing 2-13 demonstrates how to do this.-- Add FILESTREAM columnALTER TABLE [dbo].[Items]ADD ItemImage_New VARBINARY(MAX) FILESTREAM NULL-- Copy data to the new columnUPDATE [dbo].[Items] SETItemImage_New = ItemImage-- Drop the original columnALTER TABLE [dbo].[Items]DROP COLUMN ItemImage-- Rename the new column to original nameEXECUTE sp_rename@objname = '[dbo].[Items].[ItemImage_New]',@newname = 'ItemImage',@objtype = 'COLUMN'Listing 2-13:Altering a VARBINARY(MAX) column to a FILESTREAM column.A similar approach can be used to change a FILESTREAM column to a regularVARBINARY(MAX) column.67