what is the difference between tables fnd_user_resp_groups and fnd_user_resp_groups_direct ?

All the active assignments of responsibilities can be extracted by using the FND_USER_RESP_GROUPS table which combines DIRECT and INDIRECT responsibilities.

FND_USER_RESP_GROUPS_ALL lists all users and against all responsibilities they ever had even if they no longer have them.

FND_USER_RESP_GROUPS lists only the users who have current, active responsibilities

If you need only the DIRECT responsibilities than you also have the option to use the seeded view FND_USER_RESP_GROUPS_DIRECT.

If you need only the INDIRECT responsibilities (added by roles - like Application Diagnostics) then use the seeded view FND_USER_RESP_GROUPS_INDIRECT.

Source : Oracle Forums

When you tag responsibility from sysadmin then it is visible in FND_USER_RESP_GROUPS_DIRECT view.

When you create a role,in which there are multiple responsibilities present and the role is then tagged to user then those responsibilties will be visible in FND_USER_RESP_GROUPS_INDIRECT

http://www.erpschools.com/sysadmin-and-aol/user-management-role-categories-roles-indirect-responsibilities