RE: Doubt related to ROWID

From: Ric Van Dyke <ric.van.dyke_at_hotsos.com>
Date: Wed, 24 Jul 2013 18:08:28 -0500
Message-ID: <C970F08BBE1E164AA8063E01502A71CF02137A77_at_WIN02.hotsos.com>

Yes and they all appear to be index clusters (zero hash keys for all of them):

SQL> select cluster_name, hashkeys from dba_clusters order by cluster_name;

CLUSTER_NAME                          HASHKEYS
------------------------------ ---------------
C_COBJ#                                      0
C_FILE#_BLOCK#                               0
C_MLOG#                                      0
C_OBJ#                                       0
C_OBJ#_INTCOL#                               0
C_RG#                                        0
C_TOID_VERSION#                              0
C_TS#                                        0
C_USER#                                      0
SMON_SCN_TO_TIME_AUX                         0

10 rows selected.

-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Jonathan Lewis Sent: Wednesday, July 24, 2013 5:14 PM
To: 'ORACLE-L'
Subject: RE: Doubt related to ROWID

Logged on as sys:

SQL> l
  1 select cluster_name, count(*)
  2 from user_tables
  3 where cluster_name is not null
  4 group by cluster_name
  5 -- having count(*) > 1
  6* order by 1
SQL> /

CLUSTER_NAME                       COUNT(*)
-------------------------------- ----------
C_COBJ#                                   2
C_FILE#_BLOCK#                            2
C_MLOG#                                   2
C_OBJ#                                   17
C_OBJ#_INTCOL#                            1
C_RG#                                     2
C_TOID_VERSION#                           6
C_TS#                                     2
C_USER#                                   2
SMON_SCN_TO_TIME_AUX                      1

10 rows selected.

I've always thought c_obj# most educational - and it keeps growing !

Regards
Jonathan Lewis

---

From: Mark W. Farnham [mwf_at_rsiz.com]
Sent: 24 July 2013 20:49
To: Jonathan Lewis; 'Ric Van Dyke'; 'ORACLE-L' Subject: RE: Doubt related to ROWID

Cannot resist: Mission Accomplished. As self-appointed judge of geek contests I declare Jonathan has out-geeked Ric this time.

BTW, we ALL use clusters pretty much all the time:

OWNER                          CLUSTER_NAME

TABLESPACE_NAME

------------------------------ ------------------------------
------------------------------
SYS                            SMON_SCN_TO_TIME_AUX           SYSAUX
SYS                            C_COBJ#                        SYSTEM
SYS                            C_FILE#_BLOCK#                 SYSTEM
SYS                            C_MLOG#                        SYSTEM
SYS                            C_OBJ#                         SYSTEM
SYS                            C_OBJ#_INTCOL#                 SYSTEM
SYS                            C_RG#                          SYSTEM
SYS                            C_TOID_VERSION#                SYSTEM
SYS                            C_TS#                          SYSTEM
SYS                            C_USER#                        SYSTEM

If you want to go extra geeky, read the sql.bsq file (which I'm quite sure both participants in the geekiest contest have done.) The comments about what the v6 developers (architects?) thought would be sufficient size for the number of columns of the day are hilarious. (And they were very very smart persons, no doubt there. Changing times...)

mwf--
http://www.freelists.org/webpage/oracle-l

--
http://www.freelists.org/webpage/oracle-l

Received on Thu Jul 25 2013 - 01:08:28 CEST