Strapi is a headless CMS and focuses on Content Delivery to a Frontend. Fastgen is a lowcode backend builder and is putting a stronger focus on application logic, triggering workflows, and moving data around between different sources. So there can be a slight overlap but it is not very large.
If you want to query data from the connected database in Fastgen, you can do so by using our SQL action block. For your example you could use something like the following statement:
SELECT * FROM log_entries WHERE (created_by = 'Joe' OR created_by = 'Mary') AND created_at >= '2022-01-01' AND created_at < '2023-01-01';
The SQL Action would then return the requested data and you can reuse it in any of the following actions, send it to your frontend, a slack channel, a different api or any destination you want. You can also trigger additional logic or workflows based on the results.