I want to refresh my knowledge

[Sven_Born]

Have you found these already?

https://tech.forums.softwareag.com/t/how-do-i-start-learning-natural-adabas-at-home/253694/1

https://learn.softwareag.com/

https://education.softwareag.com/adabas-and-natural

https://github.com/SoftwareAG/adabas-natural-code-samples