Request to add open-source license to repository

[weiwch]

Thank the authors for such valuable work. I find the code very useful and would like to leverage it for our Apache open-source project. I am particularly grateful for your documentation that allows interested users to integrate it into their own tools to evaluate configurations on real DBMS deployments.

However, I kindly request that you add an open-source license to the repository. It would be helpful to have a clear understanding of the terms and conditions under which we can use your code. I believe this will benefit both the contributors and users of your repository.