[root@~]#su-postgres
Lastlogin:WedApr110:28:10CST2015onpts/2
-bash-4.2$psql-Upostgres
psql(9.4.0)
Type"help"forhelp.

postgres=#createuserrootwithpassword'password';
CREATEROLE
postgres=#GRANTALLPRIVILEGESONDATABASEmydatabasetoroot;
GRANT
postgres=#ALTERROLErootWITHSUPERUSER;

postgres=#\q

For personal testing only