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Home -> Community -> Mailing Lists -> Oracle-L -> RE: ORA-1578...block corrupted...error is normal...a block...had a NOLOGGING...operation performed against
Here is another test indicating that a direct-path insert to a nologging index is actually logged (like Jared has also shown), which is contrary to the documentation.
Notice that both the table and the index are created as NOLOGGING, but the tablespace containing the index (TOOLS) only gets marked as unrecoverable at the time of the index creation (16:42) and the unrecoverable time is not updated after the direct-path insert, whereas the tablespace containing the table (SYSTEM) *does* have its unrecoverable time updated at the time of the direct-path insert (16:48). So, it appears the table changes are not logged, and therefore are unrecoverable as would be expected, but the index changes *are* still logged and therefore the index is recoverable, contrary to the documentation:
SQL>create table t_nolog tablespace system nologging as select * from all_objects;
Table created.
SQL>create index t_nolog_idx on t_nolog (object_type, object_name) tablespace tools nologging;
Index created.
SQL>select tablespace_name, logging from user_tables where table_name = 'T_NOLOG';
TABLESPACE_NAME LOG ------------------------------ --- SYSTEM NO
SQL>select tablespace_name, logging from user_indexes where index_name = 'T_NOLOG_IDX';
TABLESPACE_NAME LOG ------------------------------ --- TOOLS NO
SQL>insert /*+ APPEND */ into t_nolog select * from all_objects;
3005 rows created.
SQL>commit;
Commit complete.
SQL>select name, unrecoverable_time from v$datafile;
NAME UNRECOVERABLE_TIME -------------------------------------------------- ------------------/u07/oradat/vrtxtst/vertex01.dbf
/u07/oradat/vrtxtst/system01.dbf 23-AUG-05 16:48:13
/u07/oradat/vrtxtst/undotbs01.dbf
/u07/oradat/vrtxtst/tools01.dbf 23-AUG-05 16:41:17
SQL>insert /*+ APPEND */ into t_nolog select * from all_objects;
3005 rows created.
SQL>commit;
Commit complete.
SQL>select name, unrecoverable_time from v$datafile;
NAME UNRECOVERABLE_TIME -------------------------------------------------- ------------------/u07/oradat/vrtxtst/vertex01.dbf
/u07/oradat/vrtxtst/system01.dbf 23-AUG-05 17:01:35
/u07/oradat/vrtxtst/undotbs01.dbf
/u07/oradat/vrtxtst/tools01.dbf 23-AUG-05 16:41:17
-----Original Message-----
From: Jared Still [mailto:jkstill_at_gmail.com]
Sent: Tuesday, August 23, 2005 3:25 PM
To: Allen, Brandon
Cc: oracle-l_at_freelists.org
Subject: Re: ORA-1578...block corrupted...error is normal...a block...had a NOLOGGING...operation performed against
I don't see any corruption.
Notice the index full scan below.
Also see the 10046 trace data following the test output.
15:21:49 SQL>
15:21:49 SQL>alter table nolog_test modify(owner not null, object_name not null, object_type not null);
Table altered.
15:21:49 SQL>
15:21:49 SQL>exec dbms_stats.gather_table_stats(user,tabname=>'NOLOG_TEST',cascade=>true,estimate_percent=>100)
PL/SQL procedure successfully completed.
15:21:52 SQL>
15:21:52 SQL>analyze index nolog_test_idx validate structure;
Index analyzed.
15:21:52 SQL>
15:21:52 SQL>select * from index_stats;
HEIGHT BLOCKS NAME PARTITION_NAME LF_ROWS
---------- ----------- ------------------------------ ------------------------------ ----------
LF_BLKS LF_ROWS_LEN LF_BLK_LEN BR_ROWS BR_BLKS BR_ROWS_LEN BR_BLK_LEN DEL_LF_ROWS ---------- ----------- ---------- ---------- ---------- ----------- ---------- -----------
PCT
DEL_LF_ROWS_LEN DISTINCT_KEYS MOST_REPEATED_KEY BTREE_SPACE USED_SPACE USED ROWS_PER_KEY
--------------- ------------- ----------------- ----------- ---------- ---- ------------BLKS_GETS_PER_ACCESS PRE_ROWS PRE_ROWS_LEN OPT_CMPR_COUNT OPT_CMPR_PCTSAVE
-------------------- ---------- ------------ -------------- ----------------
3 512 NOLOG_TEST_IDX 64988
481 3144140 7996 480 4 14505 8028 0
0 32355 32 3878188 3158645 82 2.00859218
4.50429609 0 0 3 32
1 row selected.
15:21:52 SQL>
15:21:52 SQL>select index_name, num_rows from user_indexes where index_name = 'NOLOG_TEST_IDX';
INDEX NAME NUM_ROWS ------------------------------ ---------- NOLOG_TEST_IDX 64988
1 row selected.
15:21:52 SQL>
15:21:52 SQL>select table_name, blocks, num_rows from user_tables where table_name = 'NOLOG_TEST';
TABLE NAME BLOCKS NUM_ROWS ------------------------------ ----------- ---------- NOLOG_TEST 960 64988
1 row selected.
15:21:52 SQL>
15:21:52 SQL>select count(*) from nolog_test;
COUNT(*)
64988
1 row selected.
15:21:52 SQL> 15:21:52 SQL>set autotrace on 15:21:52 SQL> 15:21:52 SQL>select count(*) 15:21:52 2 from ( 15:21:52 3 select owner,object_type,object_name 15:21:52 4 from nolog_test 15:21:52 5 ) 15:21:52 6 /
COUNT(*)
64988
1 row selected.
Execution Plan
0
SELECT STATEMENT Optimizer=CHOOSE (Cost=574 Card=1)
1 0
2 1
Statistics
0 recursive calls
0 db block gets
483 consistent gets
0 physical reads
0 redo size
381 bytes sent via SQL*Net to client
383 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
15:21:52 SQL>
15:21:52 SQL>set autotrace off
PARSING IN CURSOR #3 len=77 dep=0 uid=101 oct=3 lid=101 tim=1098472512646433 hv=1860683524 ad='5757265c'
select count(*)
from (
select owner,object_type,object_name
from nolog_test
)
END OF STMT
PARSE #3:c=0,e=957,p=0,cr=0,cu=0,mis=1,r=0,dep=0,og=4,tim=1098472512646418
BINDS #3:
EXEC #3:c=0,e=97,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=4,tim=1098472512646783 WAIT #3: nam='SQL*Net message to client' ela= 3 p1=1413697536 p2=1 p3=0 FETCH #3:c=20000,e=24456,p=0,cr=483,cu=0,mis=0,r=1,dep=0,og=4,tim=1098472512671338WAIT #3: nam='SQL*Net message from client' ela= 390 p1=1413697536 p2=1 p3=0 FETCH #3:c=0,e=3,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=0,tim=1098472512672047 WAIT #3: nam='SQL*Net message to client' ela= 2 p1=1413697536 p2=1 p3=0 WAIT #3: nam='SQL*Net message from client' ela= 547 p1=1413697536 p2=1 p3=0 *** SESSION ID:(9.13) 2005-08-23 15:24:13.041 STAT #3 id=1 cnt=1 pid=0 pos=1 obj=0 op='SORT AGGREGATE ' STAT #3 id=2 cnt=64988 pid=1 pos=1 obj=48350 op='INDEX FULL SCAN NOLOG_TEST_IDX '
On 8/23/05, Allen, Brandon <Brandon.Allen_at_oneneck.com> wrote: Thanks Jared, I'll do some more tests to see if I can figure out exactly what's going on. I suspect that the direct-insert is minimally logged as it says in the documentation, but perhaps there is still a signifcant amount from dictionary updates due to block splits and other recursive activity, and when you recover, the direct-inserted blocks are corrupt, but the select statement you ran for the regular (non-direct, logged) insert did not need to touch those corrupt blocks so it completed just fine - but if you forced a full index scan, you would see the corruption.
-----Original Message-----
From: Jared Still [mailto:jkstill_at_gmail.com]
Sent: Tuesday, August 23, 2005 2:47 PM
To: Allen, Brandon
Cc: oracle-l_at_freelists.org
Subject: Re: ORA-1578...block corrupted...error is normal...a block...had a NOLOGGING...operation performed against
v$datafile
FILE_NAME
------- ------------------- ---------------------
/u01/oradata/dv03/test01.dbf
ONLINE 08/23/2005 12:33:51 1039632753 ---------------------------------------------------------------
14:44:28 SQL>l
1* select * from v$backup_corruption
14:44:29 SQL>/
no rows selected
DBV: I have not included any dbv output.
dbv reports every file I test as corrupt ( including SYSTEM)
This is with the database shutdown.
Don't know what the problem there is, but I'm not going to
pursue it right now.
Jared
On 8/23/05, Allen, Brandon <Brandon.Allen_at_oneneck.com > wrote: Thanks for the great test case Jared - just a few questions:
Can you check the following to see if there is any indication of corruption due to the recovery through the nologging operation:
Have you submitted your case to Oracle support to see if it is a bug, or if we're all missing something?
Thanks again,
Brandon
-----Original Message-----
From: Jared Still [mailto: jkstill_at_gmail.com]
Sent: Tuesday, August 23, 2005 12:46 PM
To: Hemant K Chitale
Cc: Allen, Brandon; cmarquez_at_collegeboard.org; oracle-l_at_freelists.org
Subject: Re: ORA-1578...block corrupted...error is normal...a block...had a NOLOGGING...operation performed against
On 8/23/05, Hemant K Chitale <hkchital_at_singnet.com.sg> wrote:
Jared,
You ARE right. You really don't need to retest it.
Maybe not, but I want to.
Privileged/Confidential Information may be contained in this message or attachments hereto. Please advise immediately if you or your employer do not consent to Internet email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of this company shall be understood as neither given nor endorsed by it.
-- Jared Still Certifiable Oracle DBA and Part Time Perl Evangelist Privileged/Confidential Information may be contained in this message or attachments hereto. Please advise immediately if you or your employer do not consent to Internet email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of this company shall be understood as neither given nor endorsed by it. -- Jared Still Certifiable Oracle DBA and Part Time Perl Evangelist -- http://www.freelists.org/webpage/oracle-lReceived on Tue Aug 23 2005 - 19:11:55 CDT
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