Disabling db user password expiration

SELECT USERNAME, PROFILE, ACCOUNT_STATUS FROM DBA_USERS WHERE USERNAME LIKE 'TEST_%';

select resource_name,liMit from dba_profiles where profile='DEFAULT';

ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;

alter user TEST_OIM identified by Oracle123;

sql string operation: take substr before first comma

SELECT SUBSTR('abc,def,ghi', 1 ,INSTR('abc,def,ghi', ',', 1, 1)-1)
FROM DUAL;


stolen from: 
http://psoug.org/reference/substr_instr.html