SELECT banner FROM v$version WHERE banner LIKE 'Oracle%'; 
 SELECT banner FROM v$version WHERE banner LIKE 'TNS%';
 SELECT version FROM v$instance;
 SELECT user FROM dual;
 SELECT username FROM all_users ORDER BY username;
 SELECT name FROM sys.user$; 
 SELECT name, password, astatus FROM sys.user$;
 SELECT name,spare4 FROM sys.user$;
 SELECT * FROM session_privs;
 SELECT * FROM dba_sys_privs WHERE grantee = 'DBSNMP';
 SELECT grantee FROM dba_sys_privs WHERE privilege = 'SELECT ANY DICTIONARY';
 SELECT GRANTEE, GRANTED_ROLE FROM DBA_ROLE_PRIVS;
 SELECT DISTINCT grantee FROM dba_sys_privs WHERE ADMIN_OPTION = 'YES';
 SELECT UTL_INADDR.get_host_name FROM dual;
 SELECT host_name FROM v$instance;
 SELECT UTL_INADDR.get_host_address FROM dual; -- gets IP address
 SELECT UTL_INADDR.get_host_name('<insert-INternal-IP-Address-2-get-hostname>') FROM dual;
 SELECT name FROM V$DATAFILE;
 SELECT global_name FROM global_name; 
 SELECT name FROM v$database; 
 SELECT instance_name FROM v$instance;
 SELECT SYS.DATABASE_NAME FROM DUAL;
 SELECT DISTINCT owner FROM all_tables;
 SELECT column_name FROM all_tab_columns WHERE table_name = 'blah'; 
 SELECT column_name FROM all_tab_columns WHERE table_name = 'blah' and owner = 'foo'; 
 SELECT table_name FROM all_tables;
 SELECT owner, table_name FROM all_tables;
 SELECT owner, table_name FROM all_tab_columns WHERE column_name LIKE '%ColumnName%';
 SELECT username FROM (SELECT ROWNUM r, username FROM all_users ORDER BY username) WHERE r=N;
 SELECT value FROM v$parameter2 WHERE name = 'utl_file_dir';