I have a Sitecore 8.2 project that I'm upgrading to 9.1.1. I installed a fresh insistence of Sitecore 9.1.1 and moved my old project into it. I have it pointing at the old Core, Master, Web databases and everything seems to be running good. My question is should i still install the "upgrade package"? Do i need to upgrade my databases at all?
This is how I typically do upgrades...this is a bit simplistic, as it may get expansive based on your environment(s):
- Install the current Sitecore instance and connect the existing databases (core and master) to it. Do NOT publish custom code to this.
- Run the Sitecore upgrade package so that your databases get the updates they need.
- Install the new Sitecore instance and connect the upgraded core and master databases. (You don't need web, since that's just published out from the master.)
- In your codebase, update the appropriate packages and configs. Assuming you used transforms and didn't modify your base web.config from what Sitecore delivers, this should be easier. Going from 8.x to 9.x, you also need to account for the use of roles, which can make it so you convert transforms on App_Config/Include files to just use roles.
- Handle any other code changes, deprecated calls, upgrading Glass Mapper, etc etc as needed.
- Publish your upgraded code to the new instance and start testing.
That's very high level but should get you started. This way you keep your existing instance in the event of issues, as well.