This question isn't particularly suited for the dba.se site, for a couple of reasons. It's a little vague still, and it's gonna be outdated before a while. It's not good for StackOverflow for the same reason. here's a good resource for knowing what sort of things we're good at answering here and on SO.
All that being said, there's always room for real-world explanations of "how does this actually work" and I'm always happy to help people who just don't understand the larger world of licensing and such.
One thing you're missing is what version of SQL you think you should be running this on, and what licensing you're already privy to. Ostensibly you should have some sort of MSDN license for your organization, so that's a good thing to hire a consultant for understanding. We can't honestly tell every visitor exactly how to license their business and what every single visitor's needs are; this is the sort of thing to spend a few dollars on. If you're a non-profit plenty of folks out there can help, toss something on twitter with #sqlhelp and I bet you can get some help. But if you're running any sort of for-profit organization, spend the few dollars to get help. You would want to get paid too yeah?
Okay, so let's focus on the meat and potatoes of your request, now that we've gotten out of the way about "this isn't really a good question" because you're not the first person confused about this.
I already said you should pursue and MSDN, and here's the current licensing document and then this one for SQL server (notice that I just googled these things so you could too in the future now that you know how to find something about them)
From that second link:
Licensing SQL Server for non-production use
Customers are required to license every Microsoft software product they install, configure, and use, including all physical and virtual instances. As such, licensing a development and test environment can be expensive and challenging to manage as new servers are set up and others are torn down. Microsoft offers multiple, costeffective options for licensing SQL Server 2019 software for use in non-production environments.
SQL Server Developer Edition
SQL Server 2019 Developer Edition is a fully featured version of SQL Server software—including all the features and capabilities of Enterprise Edition—licensed for development, test and demonstration purposes only. SQL Server Developer Edition may not be used in a production environment. Any test data that was used for design, development or test purposes must be removed prior to deploying the software for production use. Customers may install and run the SQL Server Developer Edition software on any number of devices. This is
significant because it allows customers to run the software on multiple devices (for testing purposes, for example) without having to license each non-production server system.
Note: A production environment is defined as an environment that is accessed by end-users of an application (such as an internet website) and that is used for more than gathering feedback or acceptance testing of that
application. Other scenarios that constitute production environments include:
- Environments that connect to a production database
- Environments that support disaster-recovery or backup for a production environment
- Environments that are used for production at least some of the time, such as a server that is rotated into production during peak periods of activity
It is rare that someone whose primary role is designing, developing, or testing software would also qualify as an “end user” of the software.
Note: Effective April 1, 2016, SQL Server Developer Edition became a free product, available through the Microsoft Dev Essentials program or as software download from the SQL Server website. For customers who need prior versions and/or additional SQL Server editions for development, test and demonstration purpose (e.g. Standard or Enterprise editions), these can be accessed through Visual Studio subscriptions.
Visual Studio subscriptions
Visual Studio subscriptions Customers can also choose to license SQL Server software for non-production use through certain Visual Studio subscription offerings, including the Visual Studio Professional and Enterprise subscription levels. Visual Studio subscriptions are licensed on a per user basis and the software cannot be used in a production environment.
Just like the MS document says:
© 2019 Microsoft Corporation. All rights reserved. This document is for informational purposes only. Microsoft makes no warranties, express or implied, in this document.
I also do not warrant the information here, hence "hire someone if you're not 100% sure what you're doing."
Okay, now that we've handled that you can actually run SQL Server Developer Edition for free if you're properly licensed (see MSDN license comments) then you can indeed run DevEd for non production uses. So here's the real question you've asked:
I have couple of databases that are used for training classes every now and then
And the answer is "do you charge for that training?"
- If this is for internal training then the answer is usually no, so this can be considered non-production in most cases.
- If you are charging for this service, then the use-case is probably considered production.
Again, when in doubt, hire a professional to help you evaluate your use case. I happen to like getting paid, and I bet you do too. So do others. And plenty of people will help non-profits for free. Also, Microsoft has a lot of programs to help startups so you can seek those out if you're a startup.