From your other post, I understand that you have deployed via Docker? The first thing to do is make sure you are deploying the JDBC Connector. OpenIAM uses SOA or Microservices and the JDBC Connector “Microservice” is not deployed out of the box. You will need to make sure you’ve uncommented line 180 in the startup.sh file (https://bitbucket.org/openiam/openiam-docker-compose/src/84ec2c1cd38bbf0c6150bd3aa2ed2e8757c03df5/startup.sh#lines-180)
Out of the box you will find that the JDBC Connector is already supplied as a configured connector, you should also find an example JDBC Managed System which will help you get started.
In the search query field you need to write your SQL select statement to get users from that system and either use the Policy Map or a Transform groovy script to map the columns from the database to OpenIAM.
Hopefully that’s enough to get you going.