How to add a filestream column in the Entity Framework 4.0 model first designer?

I'm using the EF 4.0 designer to create a database by clicking on "Generate Database from Model". I wan't to use the sql 2008 column type "filestream". Unfortunately I can't select "filestream" from Type DropDownList of a specific column.

So, how do I use the filestream with EF 4.0 m开发者_运维问答odel first?

So far I've googled some SQL scripts to manually add such columns, but adding them via SQL script means that I don't have them in my model. What should I do?

Entity framework doesn't support Filestream. Even if you add it, it will still be used as any other varbinary(max) column. To use Filestream during database generation you must use custom structural annotation and modify generation template.

The varbinary(max) binary large object (BLOB) data is stored as files on the file system. There is not a sql type named FILESTREAM. It is an attribute for BLOB data stored in varbinary(MAX) columns.