BW Statistics for BW Accelerator
Hi Everyone,
Is there any standard business content to collect the statistics information for BW accelerator?
If not, can you please suggest how to collect the BWA statistics?
Thanks
Kind Regards
Anukul
ANUKUL GIRADKAR wrote:
Hi Everyone,
>
> Is there any standard business content to collect the statistics information for BW accelerator?
>
> If not, can you please suggest how to collect the BWA statistics?
>
> Thanks
>
> --
> Kind Regards
> Anukul
Oss Note "1163732 - BWA 7.00: BWA statistics index" explains it
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BR0801I BRCONNECT 7.00 (46)
BR0154E Unexpected option value 'u2013f' found at position 8
BR0154E Unexpected option value 'collect' found at position 9
BR0806I End of BRCONNECT processing: ceenwjre.log 2010-11-12 08.41.38
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BR0852I Number of tables to delete statistics: 0
BR0854I Number of tables to collect statistics without checking: 0
BR0855I Number of indexes with missing statistics: 0
BR0856I Number of indexes to delete statistics: 0
BR0857I Number of indexes to collect statistics: 0
BR0853I Number of tables to check (and collect if needed) statistics: 1
Owner SAPPRD: 1
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BR0126I Unattended mode active - no operator confirmation required
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BR0280I BRCONNECT time stamp: 2010-11-12 08.42.16
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BR0880I Statistics collected for 0/0 tables/indexes
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BR0280I BRCONNECT time stamp: 2010-11-12 08.42.17
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[http://help.sap.com/saphelp_nw70ehp1/helpdata/EN/02/0ae0c6395911d5992200508b6b8b11/content.htm|http://help.sap.com/saphelp_nw70ehp1/helpdata/EN/02/0ae0c6395911d5992200508b6b8b11/content.htm]
[http://help.sap.com/saphelp_nw70ehp1/helpdata/EN/cb/f1e33a5bd8e934e10000000a114084/content.htm|http://help.sap.com/saphelp_nw70ehp1/helpdata/EN/cb/f1e33a5bd8e934e10000000a114084/content.htm]
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BR0154E Unexpected option value 'u2013f' found at position 8
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Try again with the following statement (-f in stead of u2013f) you will see that it will work:
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Hi All,
Is there a way to manage statistics for collections used as table types in SQL.
Below is my test case
Oracle Version :
SQL> select * from v$version;
BANNER
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE 11.2.0.3.0 Production
TNS for IBM/AIX RISC System/6000: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production
SQL> Original Query :
SELECT
9999,
tbl_typ.FILE_ID,
tf.FILE_NM ,
tf.MIME_TYPE ,
dbms_lob.getlength(tfd.FILE_DATA)
FROM
TG_FILE tf,
TG_FILE_DATA tfd,
SELECT
FROM
TABLE
SELECT
CAST(TABLE_ESC_ATTACH(OBJ_ESC_ATTACH( 9999, 99991, 'file1.png', NULL, NULL, NULL),
OBJ_ESC_ATTACH( 9999, 99992, 'file2.png', NULL, NULL, NULL)) AS TABLE_ESC_ATTACH)
FROM
dual
) tbl_typ
WHERE
tf.FILE_ID = tfd.FILE_ID
AND tf.FILE_ID = tbl_typ.FILE_ID
AND tfd.FILE_ID = tbl_typ.FILE_ID;
Elapsed: 00:00:02.90
Execution Plan
Plan hash value: 3970072279
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 1 | 194 | 4567 (2)| 00:00:55 |
|* 1 | HASH JOIN | | 1 | 194 | 4567 (2)| 00:00:55 |
|* 2 | HASH JOIN | | 8168 | 287K| 695 (3)| 00:00:09 |
| 3 | VIEW | | 8168 | 103K| 29 (0)| 00:00:01 |
| 4 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | 8168 | 16336 | 29 (0)| 00:00:01 |
| 5 | FAST DUAL | | 1 | | 2 (0)| 00:00:01 |
| 6 | TABLE ACCESS FULL | TG_FILE | 565K| 12M| 659 (2)| 00:00:08 |
| 7 | TABLE ACCESS FULL | TG_FILE_DATA | 852K| 128M| 3863 (1)| 00:00:47 |
Predicate Information (identified by operation id):
1 - access("TF"."FILE_ID"="TFD"."FILE_ID" AND "TFD"."FILE_ID"="TBL_TYP"."FILE_ID")
2 - access("TF"."FILE_ID"="TBL_TYP"."FILE_ID")
Statistics
7 recursive calls
0 db block gets
16783 consistent gets
16779 physical reads
0 redo size
916 bytes sent via SQL*Net to client
524 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed Indexes are present in both the tables ( TG_FILE, TG_FILE_DATA ) on column FILE_ID.
select
index_name,blevel,leaf_blocks,DISTINCT_KEYS,clustering_factor,num_rows,sample_size
from
all_indexes
where table_name in ('TG_FILE','TG_FILE_DATA');
INDEX_NAME BLEVEL LEAF_BLOCKS DISTINCT_KEYS CLUSTERING_FACTOR NUM_ROWS SAMPLE_SIZE
TG_FILE_PK 2 2160 552842 21401 552842 285428
TG_FILE_DATA_PK 2 3544 852297 61437 852297 852297 Ideally the view should have used NESTED LOOP, to use the indexes since the no. of rows coming from object collection is only 2.
But it is taking default as 8168, leading to HASH join between the tables..leading to FULL TABLE access.
So my question is, is there any way by which I can change the statistics while using collections in SQL ?
I can use hints to use indexes but planning to avoid it as of now. Currently the time shown in explain plan is not accurate
Modified query with hints :
SELECT
/*+ index(tf TG_FILE_PK ) index(tfd TG_FILE_DATA_PK) */
9999,
tbl_typ.FILE_ID,
tf.FILE_NM ,
tf.MIME_TYPE ,
dbms_lob.getlength(tfd.FILE_DATA)
FROM
TG_FILE tf,
TG_FILE_DATA tfd,
SELECT
FROM
TABLE
SELECT
CAST(TABLE_ESC_ATTACH(OBJ_ESC_ATTACH( 9999, 99991, 'file1.png', NULL, NULL, NULL),
OBJ_ESC_ATTACH( 9999, 99992, 'file2.png', NULL, NULL, NULL)) AS TABLE_ESC_ATTACH)
FROM
dual
tbl_typ
WHERE
tf.FILE_ID = tfd.FILE_ID
AND tf.FILE_ID = tbl_typ.FILE_ID
AND tfd.FILE_ID = tbl_typ.FILE_ID;
Elapsed: 00:00:00.01
Execution Plan
Plan hash value: 1670128954
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 1 | 194 | 29978 (1)| 00:06:00 |
| 1 | NESTED LOOPS | | | | | |
| 2 | NESTED LOOPS | | 1 | 194 | 29978 (1)| 00:06:00 |
| 3 | NESTED LOOPS | | 8168 | 1363K| 16379 (1)| 00:03:17 |
| 4 | VIEW | | 8168 | 103K| 29 (0)| 00:00:01 |
| 5 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | 8168 | 16336 | 29 (0)| 00:00:01 |
| 6 | FAST DUAL | | 1 | | 2 (0)| 00:00:01 |
| 7 | TABLE ACCESS BY INDEX ROWID | TG_FILE_DATA | 1 | 158 | 2 (0)| 00:00:01 |
|* 8 | INDEX UNIQUE SCAN | TG_FILE_DATA_PK | 1 | | 1 (0)| 00:00:01 |
|* 9 | INDEX UNIQUE SCAN | TG_FILE_PK | 1 | | 1 (0)| 00:00:01 |
| 10 | TABLE ACCESS BY INDEX ROWID | TG_FILE | 1 | 23 | 2 (0)| 00:00:01 |
Predicate Information (identified by operation id):
8 - access("TFD"."FILE_ID"="TBL_TYP"."FILE_ID")
9 - access("TF"."FILE_ID"="TBL_TYP"."FILE_ID")
filter("TF"."FILE_ID"="TFD"."FILE_ID")
Statistics
0 recursive calls
0 db block gets
16 consistent gets
8 physical reads
0 redo size
916 bytes sent via SQL*Net to client
524 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed
Thanks,
BThanks Tubby,
While searching I had found out that we can use CARDINALITY hint to set statistics for TABLE funtion.
But I preferred not to say, as it is currently undocumented hint. I now think I should have mentioned it while posting for the first time
http://www.oracle-developer.net/display.php?id=427
If we go across the document, it has mentioned in total 3 hints to set statistics :
1) CARDINALITY (Undocumented)
2) OPT_ESTIMATE ( Undocumented )
3) DYNAMIC_SAMPLING ( Documented )
4) Extensible Optimiser
Tried it out with different hints and it is working as expected.
i.e. cardinality and opt_estimate are taking the default set value
But using dynamic_sampling hint provides the most correct estimate of the rows ( which is 2 in this particular case )
With CARDINALITY hint
SELECT
/*+ cardinality( e, 5) */*
FROM
TABLE
SELECT
CAST(TABLE_ESC_ATTACH(OBJ_ESC_ATTACH( 9999, 99991, 'file1.png', NULL, NULL, NULL),
OBJ_ESC_ATTACH( 9999, 99992, 'file2.png', NULL, NULL, NULL)) AS TABLE_ESC_ATTACH)
FROM
dual
) e ;
Elapsed: 00:00:00.00
Execution Plan
Plan hash value: 1467416936
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 5 | 10 | 29 (0)| 00:00:01 |
| 1 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | 5 | 10 | 29 (0)| 00:00:01 |
| 2 | FAST DUAL | | 1 | | 2 (0)| 00:00:01 |
With OPT_ESTIMATE hint
SELECT
/*+ opt_estimate(table, e, scale_rows=0.0006) */*
FROM
TABLE
SELECT
CAST(TABLE_ESC_ATTACH(OBJ_ESC_ATTACH( 9999, 99991, 'file1.png', NULL, NULL, NULL),
OBJ_ESC_ATTACH( 9999, 99992, 'file2.png', NULL, NULL, NULL)) AS TABLE_ESC_ATTACH)
FROM
dual
) e ;
Execution Plan
Plan hash value: 4043204977
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 5 | 485 | 29 (0)| 00:00:01 |
| 1 | VIEW | | 5 | 485 | 29 (0)| 00:00:01 |
| 2 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | 5 | 10 | 29 (0)| 00:00:01 |
| 3 | FAST DUAL | | 1 | | 2 (0)| 00:00:01 |
With DYNAMIC_SAMPLING hint
SELECT
/*+ dynamic_sampling( e, 5) */*
FROM
TABLE
SELECT
CAST(TABLE_ESC_ATTACH(OBJ_ESC_ATTACH( 9999, 99991, 'file1.png', NULL, NULL, NULL),
OBJ_ESC_ATTACH( 9999, 99992, 'file2.png', NULL, NULL, NULL)) AS TABLE_ESC_ATTACH)
FROM
dual
) e ;
Elapsed: 00:00:00.00
Execution Plan
Plan hash value: 1467416936
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
| 0 | SELECT STATEMENT | | 2 | 4 | 11 (0)| 00:00:01 |
| 1 | COLLECTION ITERATOR CONSTRUCTOR FETCH| | 2 | 4 | 11 (0)| 00:00:01 |
| 2 | FAST DUAL | | 1 | | 2 (0)| 00:00:01 |
Note
- dynamic sampling used for this statement (level=2)I will be testing the last option "Extensible Optimizer" and put my findings here .
I hope oracle in future releases, improve the statistics gathering for collections which can be used in DML and not just use the default block size.
By the way, are you aware why it uses the default block size ? Is it because it is the smallest granular unit which oracle provides ?
Regards,
B -
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Web sharing not working in 10.5.7?
Hi, I am attempting to use Web sharing to test websites in local, but it doesn't seem to work; whenever I connect to the MacBook using http://localhost, it fails, saying server cannot be found. Same goes when I connect using the iPod Touch, typing th
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Since loading OSI7 on my iphone 4s the podcast app won't open
can any one help me work out why the podcast app wont open after installing osi7
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My keyboard does not click as I type. I also noted that FaceTime does not ring when connecting. I do use a BlueTooth speaker when I listen to my iPad, which works fine. I have my iPad 2 upgraded to the latest iOS system. The speakers work fine when I
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When i try to start itunes i get error -45054 and it shuts down, help!
Can anyone help? i´ve searched for this error number, but there is no info on it. Thanks!