When I click from "Entities from DB" it correctly connects to DB, and it succesfully performs the introspection, so that I can see the list of tables from the side view. But within the popup I get 0 tables, 0 views and 0 mapped relations
I tried disabling cache and change some settings, and also restarting, but with no luck. How can I solve the problem?
For MySQL, you need to explicitly specify the schema name in the connection string to make JPA Buddy work.
Even though IntelliJ IDEA allows you to create a data source without specifying a target schema or even a database, JPA Buddy can only get data from an explicitly specified connection string. This limitation comes from the fact that we use JDBC driver to obtain meta information. So, in case your tables are located in the non-default schema, you need to create a new connection targeting the database and schema, as explained here https://www.jpa-buddy.com/documentation/database-connections/#non-default-schema-connection.
