The Database In-Memory Base Level feature is now available for Oracle Database 19c! Support for the Base Level feature was added to 19c in the just released 19.8 RU. As a brief review, with the Base Level feature you can use up to a 16GB column store without having to license the Database In-Memory option. This now gives anyone running Oracle Database 19c Enterprise Edition the ability to try out Database In-Memory for in-production workloads, without having to license the full Database In-Memory option first.
Simply apply the 19.8 RU and set the INMEMORY_FORCE initialization parameter to BASE_LEVEL and set the INMEMORY_SIZE parameter to a value up to 16GB. When you restart your database, the Base Level feature will then be enabled. That's really all there is to it. For more details see our previous blog post for the new Base Level feature here.
Update: The Oracle Database 19c documentation has been updated so you can get further details there as well.
If you want to see the Base Level feature in action on Oracle Database 19c then plan on attending our next Ask TOM Office Hours session on Wednesday, July 22nd at 9 am PDT. We will also answer your questions about the Base Level feature and any of your other Database In-Memory questions.