What is the best place for storing uploaded images, SQL database or disk file system? [closed]

I'm writing an application that allows users to upload images onto the server. I expect about 20 images per day all jpeg and probably not edited/resized. (This is another question, how to resize the images on the server side before storing. Maybe someone can please drop a .NET resource for that in the comment or so). I wonder now what the best place for storing uploaded images is.

  • Store the images as a file in the file system and create a record in a table with the exact path to that image.

  • Or, store the image itself in a table using an "image" or "binary data" data type of the database server.

I see advantages and disadvantages in both. I like a) because I can easily relocate the files and just have to change the table entry. On the other hand I don't like storing business data on the web server and I don't really want to connect the web server to any other datasource that holds business data (for security reasons) I like b) because all the information is in one place and easily accessible by a query. On the other hand the database will get very big very soon. Outsourcing that data could be more difficult.


Solution 1:

I generally store files on the file-system, since that's what its there for, though there are exceptions. For files, the file-system is the most flexible and performant solution (usually).

There are a few problems with storing files on a database - files are generally much larger than your average row - result-sets containing many large files will consume a lot of memory. Also, if you use a storage engine that employs table-locks for writes (ISAM for example), your files table might be locked often depending on the size / rate of files you are storing there.

Regarding security - I usually store the files in a directory that is outside of the document root (not accessible through an http request) and serve them through a script that checks for the proper authorization first.

Solution 2:

The only benefit for the option B is having all the data in one system, yet it's a false benefit! You may argue that your code is also a form of data, and therefore also can be stored in database - how would you like it?

Unless you have some unique case:

  • Business logic belongs in code.
  • Structured data belongs in database (relational or non-relational).
  • Bulk data belongs in storage (filesystem or other).

Files, Code, Data

It is not necessary to use filesystem to keep files. Instead you may use cloud storage (such as Amazon S3) or Infrastructure-as-a-service on top of it (such as Uploadcare):

https://uploadcare.com/upload-api-cloud-storage-and-cdn/

But storing files in the database is a bad idea.