Storing Images in DB - Networked Desktop Applications

Question

Related: Storing Images in DB - Yea or Nay?

After reading the above question, it seems the preferred method for image storage with databases is to store only the filepath within the database. However, most of these answers seem to focus on web servers.

In my case, I'm developing a desktop application that will be used across multiple computers within an intranet. A dedicated server will host the database, containing information related to performing tests on various equipment.

Images need to be stored on the server in some way. Would storing the images in the database be the correct approach in this case, or even the only approach?

Pros:

• Backup is limited to only the database.
• No need to open up the server's file system to the network.
• Single protocol for server information access.
• Protected file access. (User can't go in and delete all the images)

Cons

• Performance issues in future if there's too many images.

Edit: As stated in the tags, the application is being written in C#/.NET. If writing the images to the file system is an option in this case, I could use some help understanding how this is done.

Edit 2: As elaborated some in the comments below, for now I'm assuming a MySQL database, although the FileStream capabilities of SQL Server 2008 could potentially change that.

Also in my case, images will be added often, and can be considered read-only after this point since they should never be changed, and will just be read out when needed. Images will likely be small (~70k each), and I'm also considering some other binary format storage on the server, files which are ~20k each which I can likely apply the same approach for storing and retrieving.

Answer 1

I'd suggest keeping those files on disk in the file system, rather than in the database. File system for files, databases for relational data, etc.

Deliver by Web Service

Consider delivering those images to your desktop app by hosting a web service/app on that DB machine. That app's job it is to serve only images. Setup a web server on that machine with an ASP.NET application. Have an .ashx handle requests and stream the binary image. Something like this:

http://myserver/myapp/GetImage.ashx?CustomerID=123&ImageID=456

Security

If intranet security is an issue, this would be the point where you could ensure that the user is authenticated and authorized for read access to the image. Audit trails could be implemented here as well.

File System Security

Regarding security on those images, consider that NTFS gives you a lot of measures to ensure that only those who are authorized can read/delete/put files as required. The task then would be to define those roles and implement Windows security groups.

Future Needs

This approach allows you to securely consume those images from anywhere on the intranet. Perhaps this app would be migrated to a web application at some point? Perhaps a feature request comes from the customer where a web solution is appropriate?

This might sound like overkill rather than reading a blob from the database, but it's great from a security perspective. Consider your customers' and patients' expectations on privacy and security.

<%@ WebHandler Language="C#" Class="Handler" %>

public class Handler : IHttpHandler {

public void ProcessRequest (HttpContext context) 
{
    //go to the DB and get the path for this ID.
    string filePath = GetImagePath(context.Request.QueryString["ImageID"]);

    //now you have the path on disk; read the file
    byte[] imgBytes=GetBytesFromDisk(filePath);

    // send back as byte[]
    context.Response.BinaryWrite(imgBytes);
}