[ADMIN] Require security ACCESS matrix in prostgresql !!

[Potluri Srikanth]

 Hi all,
 can anyone provide me the security ACCESS matrix in prostgresql ?
 security involving ROLES, access priviledges , etc ...
 i am novice in the field of security implementation, hence i request
you if you can provide me examples or PPT or MATRIX sheet to
understand the security  in postgresql.
 Thanks in advance for your assistance and contribution.
 Regards, 
 Srikanth k Potluri 
 +63 9177444783(philippines)