Database Quick View

The total size of your database...

SELECT round( a.data_size
+ b.temp_size
+ c.redo_size
+ d.controlfile_size,4) "total_size in GB"
FROM (SELECT SUM (BYTES) / 1024 / 1024/ 1024 data_size
FROM dba_data_files) a,
(SELECT NVL (SUM (BYTES), 0) / 1024 / 1024/ 1024 temp_size
FROM dba_temp_files) b,
(SELECT SUM (BYTES) / 1024 / 1024/ 1024 redo_size
FROM SYS.v_$log) c,
(SELECT SUM (block_size * file_size_blks) / 1024/ 1024
/ 1024 controlfile_size
FROM v$controlfile) d

Find your Database Charaterset that it uses.

Select * from nls_database_parameters;


Find out if the  oracle installed is 64bit or 32 bit.

select 
   length(addr)*4 || '-bits' word_length 
from
   v$process 
where
   ROWNUM =1;


Find out if the database was originally created on 32 bit software and the converted to 64bit

select decode(instr(metadata,'B023'),0, '64bit Database','32bit Database') "DB Creation" 
from kopm$;

• KOPM$.METADATA contains ‘B023′ created in 32-bit env
• KOPM$.METADATA contains ‘B047′ created in 64-bit env

Find the version of your database

• select * from v$version;
• select * from product_component_version;
• select version FROM v$instance;

Find the location of alert log

select * FROM V$PARAMETER where name like '%background_dump_dest%';
or
select value from v$parameter where name='background_dump_dest';

SQL> desc v$diag_info;

select * from v$diag_info where name='Diag Alert';