[keycloak-user] scripts or API to query attributes from an external SQL database, but don't keep them in Keycloak?

Hi, We have a SQL database with user groups but the database cannot be used for authentication (no passwords). We want to authenticate users using AD / LDAP, but get a user's group information from the SQL database after authentication for authorization purposes (or sending to clients as custom attributes) without saving these attributes / group info in Keycloak: 1) authenticate using AD / LDAP 2) query user group info from the SQL database 3) authorize / send as custom attributes There are many user groups in the SQL database, so we don't want to maintain them in AD. Can someone please shed some light on this? Methods / examples / documentation? We are kind of new to Keycloak. Thanks and regards, Weijun