We typically recommend that you create a read-only trevor database user that Trevor can connect as. You can do this easily by running the below commands against your postgres database:
1. Create a trevor user and set a password
CREATE USER trevor WITH PASSWORD 'your_secure_password';
2. Grant read-only access to just the schemas that you would like Trevor to access:
-- As a very minimum Trevor needs to be able to connect to your database
GRANT CONNECT ON DATABASE database_you_want_to_connect_to_trevor TO trevor;
-- Trevor only needs read-only (i.e. SELECT) access.
-- If you want to see multiple schemas in Trevor you may need to run the below multiple times.
GRANT SELECT ON ALL TABLES IN SCHEMA schema_you_want_to_connect_to_trevor TO trevor;
-- also grant access to any future tables that are added to this schema (the above GRANT only applies to existing tables)
ALTER DEFAULT PRIVILEGES IN SCHEMA schema_you_want_to_connect_to_trevor GRANT SELECT ON TABLES TO trevor;