Best way to update products

Question

Hello

Some background:

We provide a complex system consisting of a large database and several programs - most written in C#, however some legacy applications are still running on MFC.

Most of the stuff we provide runs on a single server (runs SQL server and SQL Management studio 2005), however several applications can run on a number of client's computers. Updating this is a real pain, since after we update the database the outdated software is likely to break due to database changes. Updating the server software manually is one thing, however making sure all the client software works too is practically impossible, and will only get worse with time.

I am to write an updating service, which will be able to update the whole product - update the database, reinstall services and applications. (However only the programs / files /tables / etc that are actually modified should be updated. Downloading the whole product each time there is a update available is not an option. Also, some computers may only have a subset of avaliable programs installed)

First of all is there a already a good way of doing this? If there is something similar to ClickOnce that would also be able to update databases already out there I'd much rather use that.

If not, what are the best practices when it comes to updating? All and any material will be greatly appreciated.

I will need some updates to be installed on the server ASAP after the updates have been submitted, without any user input. That includes a windows service (that is running at all times) and any database changes. After these changes have been made, I will have to prevent any software that is not up to date from either accessing the parts that have been changed, or from running at all.

Any advice will be greatly appreciated - If I do have to write a system like that, I'd like to do it right.

Answer 1

Best practice would be to package the app up in an MSI and use Group Policy to push the updates out to each client.

If that's not possible then you need some way of informing the client app that it is out-of-date (simple check against a server holding the current version number would probably suffice) and refuse to work until an update patch is downloaded and installed - you could even launch this process from inside the app itself.

Answer 2

This answer may help you, I haven't personally used Wix but this seems to be along the lines of what you're looking for. Make sure to check out Lesson 4 in the linked tutorial, as this provides the details you would require.

I'm not sure where you would find best practices when it comes to updating, but in my personal opinion you shouldn't ever force a user to update unless it breaks the underlying application (like yours does). I would be very interested to hear if someone has a link to a list of best practices on this topic.

Edit

I was interested in possible best practices for updating so I started another question thread here. The general consensus in the answers is "Ask the user/client", but there may be some other details in the answers which may help you, I'm afraid I can't find any actual hard rules on the subject anywhere (which I was expecting).