Skip to main content

A list partitiong bug

Last week, I found a not-so-nice bug in 10gR2. Just try this short test case, creating a table with two list partitions, default and null:
alter session set nls_territory=America;
alter session set nls_language=American;

select version from product_component_version;

drop table th3;

prompt Creating TH3...
create table TH3
(
DF DATE,
DT DATE,
N NUMBER
)
partition by list (DT)
(
partition THTBL_CURRENT values (NULL)
tablespace USERS,
partition THTBL_OLD values (default)
tablespace USERS
)
;

prompt Loading TH3...
insert into TH3 (DF, DT, N)
values (to_date('01-01-2000', 'dd-mm-yyyy'), to_date('10-04-2008', 'dd-mm-yyyy'), 1);
insert into TH3 (DF, DT, N)
values (to_date('01-01-1000', 'dd-mm-yyyy'), to_date('01-03-3000', 'dd-mm-yyyy'), 2);
insert into TH3 (DF, DT, N)
values (to_date('10-04-2008', 'dd-mm-yyyy'), to_date('10-04-2008', 'dd-mm-yyyy'), 10);
insert into TH3 (DF, DT, N)
values (to_date('11-04-2008', 'dd-mm-yyyy'), to_date('11-04-2008', 'dd-mm-yyyy'), 11);
insert into TH3 (DF, DT, N)
values (to_date('10-04-2008', 'dd-mm-yyyy'), to_date('11-04-2008', 'dd-mm-yyyy'), 1011);
commit;
prompt 5 records loaded
prompt Done.

SELECT to_date('10.04.2008', 'dd.mm.yyyy'), N, df, dt, rowid
FROM th3
WHERE to_date('10.04.2008', 'dd.mm.yyyy')
BETWEEN DF AND dt;

SELECT to_date('10.04.2008', 'dd.mm.yyyy'), N, df, dt, rowid
FROM th3
WHERE to_date('10.04.2008', 'dd.mm.yyyy')
BETWEEN DF AND
nvl(dt,to_date('10.04.9999', 'dd.mm.yyyy'));

exit;

Although the selects should not differ in the results (there is no NULL value in dt column), they do:

SQL*Plus: Release 10.2.0.1.0 - Production on Sat Apr 12 14:59:05 2008

Copyright (c) 1982, 2005, Oracle. All rights reserved.


Connected To:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options


Session altered.


Session altered.


VERSION
--------------------------------------------------------------------------------
10.2.0.1.0
10.2.0.1.0
10.2.0.1.0
10.2.0.1.0

drop table th3
*
ERROR at line 1:
ORA-00942: table or view does not exist


Creating TH3...

Table created.

Loading TH3...

1 row created.


1 row created.


1 row created.


1 row created.


1 row created.


Commit complete.

5 records loaded
Done.

no rows selected


TO_DATE(' N DF DT ROWID
--------- ---------- --------- --------- ------------------
10-APR-08 1 01-JAN-00 10-APR-08 AAAM1CAAEAAAAGtAAA
10-APR-08 2 01-JAN-00 01-MAR-00 AAAM1CAAEAAAAGtAAB
10-APR-08 10 10-APR-08 10-APR-08 AAAM1CAAEAAAAGtAAC
10-APR-08 1011 10-APR-08 11-APR-08 AAAM1CAAEAAAAGtAAE

Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options

The same results were obtained for 10.2.0.3. However, in the 10.2.0.4 (and 11.1.0.6), it seems fixed:

SQL*Plus: Release 10.2.0.4.0 - Production on Sat Apr 12 18:45:30 2008

Copyright (c) 1982, 2007, Oracle. All Rights Reserved.


Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options


Session altered.


Session altered.


VERSION
--------------------------------------------------------------------------------
10.2.0.4.0
10.2.0.4.0
10.2.0.4.0
10.2.0.4.0

drop table th3
*
ERROR at line 1:
ORA-00942: table or view does not exist


Creating TH3...

Table created.

Loading TH3...

1 row created.


1 row created.


1 row created.


1 row created.


1 row created.


Commit complete.

5 records loaded
Done.

TO_DATE(' N DF DT ROWID
--------- ---------- --------- --------- ------------------
10-APR-08 1 01-JAN-00 10-APR-08 AAAM7pAAEAAAAGlAAA
10-APR-08 2 01-JAN-00 01-MAR-00 AAAM7pAAEAAAAGlAAB
10-APR-08 10 10-APR-08 10-APR-08 AAAM7pAAEAAAAGlAAC
10-APR-08 1011 10-APR-08 11-APR-08 AAAM7pAAEAAAAGlAAE


TO_DATE(' N DF DT ROWID
--------- ---------- --------- --------- ------------------
10-APR-08 1 01-JAN-00 10-APR-08 AAAM7pAAEAAAAGlAAA
10-APR-08 2 01-JAN-00 01-MAR-00 AAAM7pAAEAAAAGlAAB
10-APR-08 10 10-APR-08 10-APR-08 AAAM7pAAEAAAAGlAAC
10-APR-08 1011 10-APR-08 11-APR-08 AAAM7pAAEAAAAGlAAE

Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options


If you create the table as nonpartitioned, you get correct results irrespective of version.

Tested on Windows 32-bit (on 10.2.0.1, 10.2.0.3 and 10.2.0.4) and RHEL 5.1 x86_64 (10.2.0.3).

If you are curious, here's the explain plan (10.2.0.3) for the first select:
PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Plan hash value: 4063410327

---------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
---------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 43 | 2 (0)| 00:00:01 | | |
| 1 | PARTITION LIST EMPTY| | 1 | 43 | 2 (0)| 00:00:01 |INVALID|INVALID|
|* 2 | TABLE ACCESS FULL | TH3 | 1 | 43 | 2 (0)| 00:00:01 |INVALID|INVALID|
---------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


2 - filter("DF"<=TO_DATE('2008-04-10 00:00:00', 'yyyy-mm-dd hh24:mi:ss') AND "DT">=TO_DATE('2008-04-10 00:00:00', 'yyyy-mm-dd hh24:mi:ss'))

Note
-----
- dynamic sampling used for this statement

On 10.2.0.4, I get:
PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Plan hash value: 3503314195

---------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
---------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 43 | 3 (0)| 00:00:01 | | |
| 1 | PARTITION LIST SINGLE| | 1 | 43 | 3 (0)| 00:00:01 |KEY |KEY |
|* 2 | TABLE ACCESS FULL | TH3 | 1 | 43 | 2 (0)| 00:00:01 | 2 | 2|
---------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


2 - filter("DF"<=TO_DATE('2008-04-10 00:00:00', 'yyyy-mm-dd hh24:mi:ss') AND "DT">=TO_DATE('2008-04-10 00:00:00', 'yyyy-mm-dd hh24:mi:ss'))

Note
-----
- dynamic sampling used for this statement

So it looks like a problem in partition elimination - on 10.2.0.3, Oracle didn't evaluate the involved partitions properly.

No patch was provided by Oracle, as we have two luxurious options: a workaround and 10.2.0.4. And of course, the second select is after all the correct one for the initial problem...
Labels:

Comments

Post a Comment

Popular posts from this blog

ORA-27048: skgfifi: file header information is invalid

I was asked to analyze a situation, when an attempt to recover a 11g (standby) database resulted in bunch of "ORA-27048: skgfifi: file header information is invalid" errors. I tried to reproduce the error on my test system, using different versions (EE, SE, 11.1.0.6, 11.1.0.7), but to no avail. Fortunately, I finally got to the failing system: SQL> recover standby database; ORA-00279: change 9614132 generated at 11/27/2009 17:59:06 needed for thread 1 ORA-00289: suggestion : /u01/flash_recovery_area/T1/archivelog/2009_11_27/o1_mf_1_208_%u_.arc ORA-27048: skgfifi: file header information is invalid ORA-27048: skgfifi: file header information is invalid ORA-27048: skgfifi: file header information is invalid ORA-27048: skgfifi: file header information is invalid ORA-27048: skgfifi: file header information is invalid ORA-27048: skgfifi: file header information is invalid ORA-00280: change 9614132 for thread 1 is in sequence #208 Interestingly, nothing interesting is written to...
Post a Comment
Read more

Multitenant and standby: recover from subsetting

In the previous post we learnt how to exclude a PDB (or a datafile) from the standby database recovery. Of course, that might not be the real end goal. We may just want to skip it for now, but have the standby continue to be up-to-date for every other PDB, and eventually include the new PDB as well. Again, standard Oracle pre-12c DBA knowledge is helpful here. These files are just missing datafiles and thus a backup can be used to restore them. The new 12c features add some quirks to this process, but the base is just sound backup and recovery. Backup So let's start with a proper backup: rman target=/ Recovery Manager: Release 12.1.0.2.0 - Production on Mon Nov 16 12:42:38 2015 Copyright (c) 1982, 2014, Oracle and/or its affiliates. All rights reserved. backup database; connected to target database: CDB2 (DBID=600824249) Starting backup at 16-NOV-15 using target database control file instead of recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=193...
Post a Comment
Read more

Multitenant and standby: subsetting

In the previous post we looked at managing new PDBs added to a standby database, by copying the files to the DR server, as required. However, there is another possible approach, and that is to omit the PDB from the standby configuration altogether. There are two ways of achieving this: 1. Do it the old-school way. A long time before 12c arrived on the scene one could offline a datafile on the standby database to remove it. The same trick is used in TSPITR (tablespace point-in-time recovery), so that you don't need to restore and recover the entire database if you are only after some tablespaces. 2. 12.1.0.2 adds the option to automatically exclude the PDB from standby(s). And 12.2 adds the option to be more specific in case of multiple standbys. For the sake of curiosity I started by setting standby file management to manual again. What I found is that there was very little difference, and the steps to take are exactly the same - it’s just the error message that is slightly ...
Post a Comment
Read more