How to subset/clone the production database for development and testing

There are two databases used - Oracle and MS SQL Server. The database size in production may be few terabytes or more and it takes a very long time to copy the same in development environment. We need to run tests in development and testing environment but this copying the whole database takes a lot of time. Moreover, we don't need the whole data but a subset of it only. May be few GB. Need some suggestion as what could be the best approach here -

1. Does it make sense to create a dev/test database by selecting the required data from prod DB and have a copy of it intact. Then clone/copy the same whenever you need one and dump later. Unable to analyse if this approach has some pros and cons and make some sense.

2. Second, I could think of is using in-memory database but not sure how good that will be and how best it will fit here. I read somewhere that it's not a good practice to use in-memory database for testing as if there is any change in prod db, same change needs to be replicated in in-memory database script.

3. Someone suggested using docker container. I am new and not sure if that makes sense and how easy or difficult it would be.

Any suggestions would be a great help !!