Proper using of index for parallel statement execution

Hi all,
I've created index for my table
CREATE INDEX ZOO.rep184_med_arcdate ON ZOO.rep184_mediate(arcdate);It was before I started to think about parallel statement execution. As far as I've heard I should alter my index for proper using with parallel hint. Could you please suggest the way to go?

marco wrote:
Hi all,
I've created index for my table
CREATE INDEX ZOO.rep184_med_arcdate ON ZOO.rep184_mediate(arcdate);It was before I started to think about parallel statement execution. As far as I've heard I should alter my index for proper using with parallel hint. Could you please suggest the way to go?when all else fails Read The Fine Manual
http://download.oracle.com/docs/cd/E11882_01/server.112/e17118/sql_elements006.htm#autoId63

Similar Messages

Use Secoandary Index for VBFA for fast execution .

HI all,
           How can i use secoandary index for VBFA table to improve my select statement performance
in ALV report.below statement executing very slow.
SELECT
       vbelv
       POSNV
      vbtyp_v
      vbeln
      POSNN
      vbtyp_n
FROM VBFA
INTO TABLE IT_TY_SD_FLOW_do
FOR ALL ENTRIES IN IT_INV
WHERE VBELN = IT_INV-VBELN
AND   POSNV = IT_INV-POSNR
AND   VBTYP_N = 'M'
AND   VBTYP_V = 'J'.

Your query will never be optimized if you do not check first whether your internal table used in the where clause has at least one row.
If the table is empty you end up with a full table scan and this cannot be your objective.
Have fun.

Total space used by indexes for specific schema

Hi all.
Running Oracle 9.2.0.4.
Is there a way I can see how much index space is used for a specific schema? I query index_stats and it returns 0 rows but my stats were updated this morning.
Any input is apreciated.
Thanks

Hi,
Index space and index stats are two different things.
What you are interested to know?
1) How much space is used by index for a particular schema
select sum(bytes)/1024/1024 from dba_segments
where (owner, segment_name) in
(select owner, index_name from dba_indexes where
owner = '<schema you are interested in>')2) Is the stats gathered on index
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Data Driven Subscriptions Error - the query processor could not start the necessary thread resources for parallel query execution

Hi,
We are getting the following error when certain data driven subscriptions are fired off: "the query processor could not start the necessary thread resources for parallel query execution". I've read other posts that have the same error, and
the solution usually involves adjusting MaxDOP to limit the number of queries that are fired off in parallel.
Unfortunately, we cannot change this setting on our server for performance reasons (outside of data driven subscriptions, it negatively impacts our ETL processing times). We tried putting query hints like "OPTION (MAXDOP 2);" in the reports
that are causing the error, but it did not resolve the problem.
Are there any settings within Reporting Services that can be adjusted to limit the number of subscriptions that get fired off in parallel?
Any help is appreciated - thanks!

Yes, that is correct. It's a painful problem, because you don't know which specific subscription failed. For example, we have a data driven subscription that sends out about 800 emails. Lately, we've been having a handful of them fail. You don't know
which ones out of the 800 failed though, even from the RS log files - all it tells you is that "the
query processor could not start the necessary thread resources for parallel query execution".
Thanks, I'll try changing <MaxQueueThreads> and will let you know if it works.
On a side note: I've noticed that it is only reports with cascading parameters (ex. where parameter 2 is dependent on the selection from parameter 1) that get this error message...

Why is the Star Transformation using two indexes for the same dimension?

Hi,
Recently, I have made an investigation about the Star Transformation feature. I have found a strange test case, which plays an important role in my strategy for our overall DWH architecture. Here it is:
The Strategy:
I would like to have the classical Star Transformation approach (single column Bitmap Indexes for each dimension foreign key column in the fact table), together with additional Bitmap Join Indexes for some of the dimension attributes, which would benefit from the materialization of the join (bitmap merge operation will be skipped/optimized).
The query:
select dp.brand, ds. region_name, dc.region_name
     , count(*), sum(f.extended_price)
from fact_line_item f
     , dim_part       dp
     , dim_supplier   ds
     , dim_customer   dc
where dp.mfgr        = 10                 -- dimension selectivity = 1/10 --> acttual/fact selectivity = 6/10
   and f.part_dk      = dp.dk
   and ds.region_name = 'REGION #1' -- dimension selectivity = 1/9
   and f.supplier_dk = ds.dk
   and dc.region_name = 'REGION #1' -- dimension selectivity = 1/11
   and f.customer_dk = dc.dk
group by dp.brand, ds. region_name, dc.region_name
The actual plan:
| Id | Operation                              | Name                        | Starts | E-Rows | Cost (%CPU)| A-Rows |   A-Time   | Buffers | Reads |
|   0 | SELECT STATEMENT                       |                             |      1 |        | 3247 (100)|      1 |00:01:42.05 |     264K|    220K|
|   1 | HASH GROUP BY                         |                             |      1 |      2 | 3247   (1)|      1 |00:01:42.05 |     264K|    220K|
|* 2 |   HASH JOIN                            |                             |      1 | 33242 | 3037   (1)|    217K|00:01:29.67 |     264K|    220K|
|* 3 |    TABLE ACCESS FULL                   | DIM_SUPPLIER                |      1 |   1112 |   102   (0)|   1112 |00:00:00.01 |     316 |      4 |
|* 4 |    HASH JOIN                           |                             |      1 | 33245 | 2934   (1)|    217K|00:01:29.10 |     264K|    220K|
|* 5 |     TABLE ACCESS FULL                  | DIM_CUSTOMER                |      1 |    910 |   102   (0)|    910 |00:00:00.08 |     316 |      8 |
|* 6 |     HASH JOIN                          |                             |      1 | 33248 | 2831   (1)|    217K|00:01:28.57 |     264K|    220K|
|* 7 |      TABLE ACCESS FULL                 | DIM_PART                    |      1 |     10 |     3   (0)|     10 |00:00:00.01 |       6 |      0 |
|   8 |      PARTITION RANGE ALL               |                             |      1 | 36211 | 2827   (1)|    217K|00:01:28.01 |     264K|    220K|
|   9 |       TABLE ACCESS BY LOCAL INDEX ROWID| FACT_LINE_ITEM              |      6 | 36211 | 2827   (1)|    217K|00:01:33.85 |     264K|    220K|
| 10 |        BITMAP CONVERSION TO ROWIDS     |                             |      6 |        |            |    217K|00:00:07.09 |   46980 |   3292 |
| 11 |         BITMAP AND                     |                             |      6 |        |            |     69 |00:00:08.33 |   46980 |   3292 |
| 12 |          BITMAP MERGE                  |                             |      6 |        |            |    193 |00:00:02.09 |    2408 |   1795 |
| 13 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   4330 |00:00:04.66 |    2408 |   1795 |
| 14 |            BUFFER SORT                 |                             |      6 |        |            |     60 |00:00:00.01 |       6 |      0 |
|* 15 |             TABLE ACCESS FULL          | DIM_PART                    |      1 |     10 |     3   (0)|     10 |00:00:00.01 |       6 |      0 |
|* 16 |            BITMAP INDEX RANGE SCAN     | FACT_LI__P_PART_DIM_KEY_BIX |     60 |        |            |   4330 |00:00:02.11 |    2402 |   1795 |
|* 17 |          BITMAP INDEX SINGLE VALUE     | FACT_LI__P_PART_MFGR_BJX    |      6 |        |            |   1747 |00:00:06.65 |     890 |    888 |
| 18 |          BITMAP MERGE                  |                             |      6 |        |            |    169 |00:00:02.78 |   16695 |    237 |
| 19 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   5460 |00:00:01.56 |   16695 |    237 |
| 20 |            BUFFER SORT                 |                             |      6 |        |            |   5460 |00:00:00.02 |     316 |      0 |
|* 21 |             TABLE ACCESS FULL          | DIM_CUSTOMER                |      1 |    910 |   102   (0)|    910 |00:00:00.01 |     316 |      0 |
|* 22 |            BITMAP INDEX RANGE SCAN     | FACT_LI__P_CUST_DIM_KEY_BIX |   5460 |        |            |   5460 |00:00:02.07 |   16379 |    237 |
| 23 |          BITMAP MERGE                  |                             |      6 |        |            |    170 |00:00:03.65 |   26987 |    372 |
| 24 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   6672 |00:00:02.23 |   26987 |    372 |
| 25 |            BUFFER SORT                 |                             |      6 |        |            |   6672 |00:00:00.01 |     316 |      0 |
|* 26 |             TABLE ACCESS FULL          | DIM_SUPPLIER                |      1 |   1112 |   102   (0)|   1112 |00:00:00.01 |     316 |      0 |
|* 27 |            BITMAP INDEX RANGE SCAN     | FACT_LI__S_SUPP_DIM_KEY_BIX |   6672 |        |            |   6672 |00:00:02.74 |   26671 |    372 |
The Question:
Why is the Star Transformation using both indexes FACT_LI__P_PART_DIM_KEY_BIX and FACT_LI__P_PART_MFGR_BJX for the same dimension criteria (dp.mfgr = 10)?? The introduction of the additional Bitmap Join Index actually make Oracle to do the work twice !!!
Anybody, any idea ?!?

Dom, here it is the plan with the predicates:
| Id | Operation                              | Name                        | Starts | E-Rows | Cost (%CPU)| A-Rows |   A-Time   | Buffers | Reads |
|   0 | SELECT STATEMENT                       |                             |      1 |        | 3638 (100)|      1 |00:06:41.17 |     445K|    236K|
|   1 | HASH GROUP BY                         |                             |      1 |      2 | 3638   (1)|      1 |00:06:41.17 |     445K|    236K|
|* 2 |   HASH JOIN                            |                             |      1 | 33242 | 3429   (1)|    217K|00:08:18.02 |     445K|    236K|
|* 3 |    TABLE ACCESS FULL                   | DIM_SUPPLIER                |      1 |   1112 |   102   (0)|   1112 |00:00:00.03 |     319 |    313 |
|* 4 |    HASH JOIN                           |                             |      1 | 33245 | 3326   (1)|    217K|00:08:17.47 |     445K|    236K|
|* 5 |     TABLE ACCESS FULL                  | DIM_CUSTOMER                |      1 |    910 |   102   (0)|    910 |00:00:00.01 |     319 |    313 |
|* 6 |     HASH JOIN                          |                             |      1 | 33248 | 3223   (1)|    217K|00:08:16.63 |     445K|    236K|
|* 7 |      TABLE ACCESS FULL                 | DIM_PART                    |      1 |     10 |     3   (0)|     10 |00:00:00.01 |       6 |      0 |
|   8 |      PARTITION RANGE ALL               |                             |      1 | 36211 | 3219   (1)|    217K|00:08:16.30 |     445K|    236K|
|   9 |       TABLE ACCESS BY LOCAL INDEX ROWID| FACT_LINE_ITEM              |      6 | 36211 | 3219   (1)|    217K|00:08:40.89 |     445K|    236K|
| 10 |        BITMAP CONVERSION TO ROWIDS     |                             |      6 |        |            |    217K|00:00:32.00 |   46919 | 19331 |
| 11 |         BITMAP AND                     |                             |      6 |        |            |     69 |00:00:34.50 |   46919 | 19331 |
| 12 |          BITMAP MERGE                  |                             |      6 |        |            |    193 |00:00:00.58 |    2353 |      1 |
| 13 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   4330 |00:00:00.10 |    2353 |      1 |
| 14 |            BUFFER SORT                 |                             |      6 |        |            |     60 |00:00:00.01 |       6 |      0 |
|* 15 |             TABLE ACCESS FULL          | DIM_PART                    |      1 |     10 |     3   (0)|     10 |00:00:00.01 |       6 |      0 |
|* 16 |            BITMAP INDEX RANGE SCAN     | FACT_LI__P_PART_DIM_KEY_BIX |     60 |        |            |   4330 |00:00:00.07 |    2347 |      1 |
|* 17 |          BITMAP INDEX SINGLE VALUE     | FACT_LI__P_PART_MFGR_BJX    |      6 |        |            |   1747 |00:01:23.64 |     882 |    565 |
| 18 |          BITMAP MERGE                  |                             |      6 |        |            |    169 |00:00:09.14 |   16697 |   7628 |
| 19 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   5460 |00:00:02.19 |   16697 |   7628 |
| 20 |            BUFFER SORT                 |                             |      6 |        |            |   5460 |00:00:00.01 |     316 |      0 |
|* 21 |             TABLE ACCESS FULL          | DIM_CUSTOMER                |      1 |    910 |   102   (0)|    910 |00:00:00.01 |     316 |      0 |
|* 22 |            BITMAP INDEX RANGE SCAN     | FACT_LI__P_CUST_DIM_KEY_BIX |   5460 |        |            |   5460 |00:00:08.78 |   16381 |   7628 |
| 23 |          BITMAP MERGE                  |                             |      6 |        |            |    170 |00:00:21.46 |   26987 | 11137 |
| 24 |           BITMAP KEY ITERATION         |                             |      6 |        |            |   6672 |00:00:10.29 |   26987 | 11137 |
| 25 |            BUFFER SORT                 |                             |      6 |        |            |   6672 |00:00:00.01 |     316 |      0 |
|* 26 |             TABLE ACCESS FULL          | DIM_SUPPLIER                |      1 |   1112 |   102   (0)|   1112 |00:00:00.01 |     316 |      0 |
|* 27 |            BITMAP INDEX RANGE SCAN     | FACT_LI__S_SUPP_DIM_KEY_BIX |   6672 |        |            |   6672 |00:00:20.94 |   26671 | 11137 |
Predicate Information (identified by operation id):
   2 - access("F"."SUPPLIER_DK"="DS"."DK")
   3 - filter("DS"."REGION_NAME"='REGION #1')
   4 - access("F"."CUSTOMER_DK"="DC"."DK")
   5 - filter("DC"."REGION_NAME"='REGION #1')
   6 - access("F"."PART_DK"="DP"."DK")
   7 - filter("DP"."MFGR"=10)
15 - filter("DP"."MFGR"=10)
16 - access("F"."PART_DK"="DP"."DK")
17 - access("F"."SYS_NC00017$"=10)
21 - filter("DC"."REGION_NAME"='REGION #1')
22 - access("F"."CUSTOMER_DK"="DC"."DK")
26 - filter("DS"."REGION_NAME"='REGION #1')
27 - access("F"."SUPPLIER_DK"="DS"."DK")
Note
   - star transformation used for this statement

Updating a column using deleted/inserted during update statement execution

I need to capture the old value while update statement is executed. I can not insert into temp table (there are many samples online where you can use OUTPUT clause to insert data in same table or another temp table)
something like
declare @count table
id int,
changed varchar (50)
insert into @count (id,changed) values (2,'T')
insert into @count (id,changed) values (3,'T')
insert into @count (id,changed) values (4,'T')
select * from @count
UPDATE @count
SET id=5,
Changed = GETDATE() -- here instead of date, I want to get inserted.id and deleted.id
OUTPUT inserted.id,
deleted.id
where id = 2
SELECT *FROM @count
Any help on this will be very much appreciated....

I am not sure to follow your question but you can get the old value just by doing:
UPDATE @count
SET id=5,
Changed = id
OUTPUT inserted.id,
deleted.id
WHERE id = 2;
since SQL Server uses all-at-once operations.
Microsoft SQL Server 2012 T-SQL Fundamentals
http://shop.oreilly.com/product/0790145321978.do
AMB
Some guidelines for posting questions...

Why is this query not using my index ?

hey
i have the following situation
(i'm sorry but i can't add the acctual script or output)
create table x as
select      level high_card ,
     mod(level,1000) medium_card ,
     mod(level,10) low_card ,
     '***' padding
from     dual
connect by level < 100001;
create index x_med_low_ix on x(low_card,medium_card);
create index x_high_ix on x(high_card);
exec dbms_stats.gather_table_stats(user,'x',cascade=>true,method_opt=>'for all indexed columns size auto');
i'm running the following query
select      *
from      x
where      low_card = 70
and     medium_card = 70
and     high_card = 70;
i'm expecting a range scan on the x_high_ix index. the optimizer expects only one row. the stats on the high_card columns shows that (num_rows * density = 1).
when i run the query the optimizer uses the x_med_low_ix and does 14 cr.
when i force the use of x_high_ix the cr goes down to 4.
i don't want to declare x_high_ix as unique.
so, why isn't he using my index ?

It's using that index for me:
SQL> create table x as
2 select level high_card ,
3 mod(level,1000) medium_card ,
4 mod(level,10) low_card ,
5 '***' padding
6 from dual
7 connect by level < 100001;
Table created.
SQL>
SQL> create index x_med_low_ix on x(low_card,medium_card);
Index created.
SQL>
SQL> create index x_high_ix on x(high_card);
Index created.
SQL>
SQL> exec dbms_stats.gather_table_stats(user,'x',cascade=>true,method_opt=>'for all indexed columns
size auto');
PL/SQL procedure successfully completed.
SQL> ed
Wrote file afiedt.buf
1   select *
2   from x
3   where low_card = 70
4   and medium_card = 70
5* and high_card = 70
SQL>
SQL> /
no rows selected
Execution Plan
Plan hash value: 775193209
| Id | Operation                   | Name      | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT            |           |     1 |    15 |     2   (0)| 00:00:01 |
|* 1 | TABLE ACCESS BY INDEX ROWID| X         |     1 |    15 |     2   (0)| 00:00:01 |
|* 2 |   INDEX RANGE SCAN          | X_HIGH_IX |     1 |       |     1   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   1 - filter("LOW_CARD"=70 AND "MEDIUM_CARD"=70)
   2 - access("HIGH_CARD"=70)
Statistics
          0 recursive calls
          0 db block gets
          3 consistent gets
          0 physical reads
          0 redo size
        454 bytes sent via SQL*Net to client
        370 bytes received via SQL*Net from client
          1 SQL*Net roundtrips to/from client
          0 sorts (memory)
          0 sorts (disk)
          0 rows processed
SQL> set autot off
SQL> select * from v$version;
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod
PL/SQL Release 10.2.0.1.0 - Production
CORE    10.2.0.1.0      Production
TNS for 32-bit Windows: Version 10.2.0.1.0 - Production
NLSRTL Version 10.2.0.1.0 - Productionwhat is your version?
By the way, when i force optimizer to use index X_MED_LOW_IX, it does 2 CR for me.

How can I create index(uniqie index) for a existed table?

Hi guys,
I want to create a index for a existed table, it should be unique index. I did it using se11, "indexes," and select the radio button "unqiue index", of course the fields as well. But when I activate it, I get a waring and therefore can not create this index. But if I select radio button "non-uniqe index", it works.
However I have to reate a unqiue index.
How can I do it?
Thanks in advance
Regards,
Liying

HI Wang
You can create your index via SE11, enter the table name, click change, choose Go To, Indexes. Here create your index with the key fields that you want. To use the index, your select statement WHERE clause, you must have the key fields of the index in the order that they appear in the index. The "optimizer" will choose the index depending on your fields of the WHERE clause.
One thing to remember is that when you create indexes for tables, the update or insert of these tables may have a slower response then before, I for one have never seen a big problem as of yet.
this Document may help u on primary and secondary indexes :
http://jdc.joy.com/helpdata/EN/cf/21eb20446011d189700000e8322d00/frameset.htm
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21eb47446011d189700000e8322d00/content.htm
If it helps Reward the points
Regards,
Rk
Message was edited by:
Rk Pasupuleti

Why isn't my query using the index?

I have a query that inserts values for engines in a grid; it uses a static date table to determine the day in week, or
week in year (depending on different standards, the DBA can configure this table to their business's likings). I have
two indexes on this table:
create table d_date (
     date_key number(5) not null,
     sql_calendar_date timestamp(3) null,
     year_id number(5) null,
     month_id number(3) null,
     day_id number(3) null,
     year_end_biz_date timestamp(3) null,
     qtr_end_biz_date timestamp(3) null,
     month_end_biz_date timestamp(3) null,
     week_end_biz_date timestamp(3) null,
     quarter_id number(3) null,
     week_id number(3) null,
     day_in_year number(5) null,
     day_in_month number(3) null,
     day_in_week number(3) null,
     month_name char(3) null,
     day_in_week_name char(3) null,
     month_type_code char(1) null,
     week_type_code char(1) null,
     date_type_code char(1) null,
     weekend_flag char(1) null,
     holiday_flag char(1) null,
     from_datetime timestamp(3) null,
     to_datetime timestamp(3) null,
     current_flag char(1) null,
     constraint d_date_pkey primary key (date_key)
     ) tablespace dim;
create index d_date_dy on d_date(year_id, day_in_year) tablespace_dim_idx;
create index d_date_ww on d_date(year_id, week_id) tablespace_dim_idx;Now, when I run a query to insert the week id into a table based on two values, the year_key and day_in_year_key,
it should use the d_date_dy index correct?
Here is what the query looks like:
INSERT INTO F_ENGINE (YEAR_KEY,MONTH_KEY,WEEK_IN_YEAR_KEY,DAY_IN_YEAR_KEY,DAY_IN_MONTH_KEY,HOUR_IN_DAY_KEY, Q_HOUR_IN_DAY_KEY,
GRID_KEY,ENGINE_KEY,TIME_STAMP,ENGINE_CPU_UTIL,ENGINE_CPU_GRID_UTIL,MEMORY_TOTAL_BYTE, MEMORY_FREE_BYTE,DISK_FREE_MEGABYTE,
PROCESS_COUNT,ENGINE_ID,GRID_ID,GRID_NAME,BATCH_ID,RECORD_VIEWABLE_F)
SELECT EXTRACT(YEAR FROM START_DATETIME),EXTRACT(MONTH FROM START_DATETIME), DD.WEEK_ID,
TO_NUMBER(TO_CHAR(START_DATETIME, 'DDD')), EXTRACT(DAY FROM START_DATETIME),EXTRACT(HOUR FROM START_DATETIME),
FLOOR(EXTRACT(MINUTE FROM START_DATETIME)/15)*15,DG.GRID_KEY,DE.ENGINE_KEY, START_DATETIME,CPU_UTIL,DS_CPU,MEMORY,
FREE_MEMORY,FREE_DISK,PROCESSES,ID,PE.GRID,DG.GRID_NAME,:B1 ,1
FROM P_ENGINE PE, D_GRID DG, D_ENGINE DE, D_DATE DD
WHERE PE.GRID = DG.GRID_ID AND DG.CURRENT_FLAG = 'Y' AND PE.ID = DE.ENGINE_ID AND DE.GRID_KEY = DG.GRID_KEY AND
DE.CURRENT_FLAG = 'Y' AND PE.BATCH_ID = :B1 AND DD.YEAR_ID = EXTRACT(YEAR FROM START_DATETIME) AND
DD.DAY_IN_YEAR = TO_NUMBER(TO_CHAR(START_DATETIME,'DDD'))
ORDER BY EXTRACT(YEAR FROM START_DATETIME),EXTRACT(MONTH FROM START_DATETIME),
EXTRACT(DAY FROM START_DATETIME),EXTRACT(HOUR FROM START_DATETIME),FLOOR(EXTRACT(MINUTE FROM START_DATETIME)/15)*15,
DG.GRID_KEY,DE.ENGINE_KEY
Here is the explain plan:
Operation Object Object Type Order Rows Size (KB) Cost Time (sec) CPU Cost I/O Cost
INSERT STATEMENT
SORT ORDER BY
     HASH JOIN
       HASH JOIN
         HASH JOIN
          TABLE ACCESS FULL D_GRID TABLE 1 2 0.316 3 1 36887 3
          TABLE ACCESS FULL D_ENGINE TABLE 2 10 0.410 3 1 42607 3
         PARTITION LIST SINGLE   5 1434 344.496 9 1 2176890 9
          TABLE ACCESS FULL P_ENGINE TABLE 4 1434 344.496 9 1 2176890 9
            TABLE ACCESS FULL D_DATE TABLE 7 7445 283.550 19 1 3274515 18Now it is obviously not using the index for the d_date table since it is doing a full table access.
Does this have something to do with the fact that I am using extract(), to_number(), to_char() functions in my WHERE clause that it is not allowing the use of the index?
Any help would be greatly appreciated. Thanks.
-Tim

It's difficult to tell just from this. For one thing, you didn't post your query using the forum format tags, so it's hard to read and you didn't post your Oracle version.
In the query, you don't always prefix columns with the table alias. That makes it impossible for us (and maintainers of this code) to know at a glance which table a column is in.
It's possible that performing functions on a column will disable the index. Do your other tables have indexes? Do you have updated statistics on all the tables?
The main reason the optimizer will not use an index is because it thinks it cheaper not to.

Framework for parallel processing

Hello,
Can anyone help me by giving some links or examples as to how to use the framework for parallel processing ?? (FPP)
My scenario is that I have a report that handles huge volumes of data and process it. But at present my report is not able to handle huge volume and it either dumps or hangs. So I would want to use the parallel processing framework which would then can handle huge volumes and also reduce the time for execution.
Thanks and Regards,
Sandhya

Is there anyone can provide some comments?

Muti sql statements execution issue   with DB2 - iSeries

Hello,
I am encountering "[SQL0104] Token ; was not valid. Valid tokens: ). " error , when I execute below statement.
Using ; (semi colon) for sql statements separation.
Please let me know , how to fix it.
Thanks in advance.
<cfquery name="qInsertTo" datasource="dsn">
    <cfloop from="1" to="25" index="i">
        insert into test1(userId,firstname) values('xx#i#','fname#i#') ;
    </cfloop>
</cfquery>
PS: I don't want to keep cfloop outside cfquery.

Hi,
trhat would be possible for an Unix System ... but I'm on a Windows OS system and I already assign everybody with full modification rights ...
Thanks anyway for ur help I'll recheck it anyway sometimes its strange ...
greetings Lars

Can I refactor this query to use an index more efficiently?

I have a members table with fields such as id, last name, first name, address, join date, etc.
I have a unique index defined on (last_name, join_date, id).
This query will use the index for a range scan, no sort required since the index will be in order for that range ('Smith'):
SELECT members.*
        FROM members
        WHERE last_name = 'Smith'
        ORDER BY joindate, idIs there any way I can get something like the following to use the index (with no sort) as well:
SELECT members.*
        FROM members
        WHERE last_name like 'S%'
        ORDER BY joindate, idI understand the difficulty is probably; even if it does a range scan on every last name 'S%' (assuming it can?), they're not necessarily in order. Case in point:
Last_Name: JoinDate:
Smith          2/5/2010
Smuckers     1/10/2010An index range scan of 'S%' would return them in the above order, which is not ordered by joindate.
So is there any way I can refactor this (query or index) such that the index can be range scanned (using LIKE 'x%') and return rows in the correct order without performing a sort? Or is that simply not possible?

xaeryan wrote:
I have a members table with fields such as id, last name, first name, address, join date, etc.
I have a unique index defined on (last_name, join_date, id).
This query will use the index for a range scan, no sort required since the index will be in order for that range ('Smith'):
SELECT members.*
FROM members
WHERE last_name = 'Smith'
ORDER BY joindate, idIs there any way I can get something like the following to use the index (with no sort) as well:
SELECT members.*
FROM members
WHERE last_name like 'S%'
ORDER BY joindate, idI understand the difficulty is probably; even if it does a range scan on every last name 'S%' (assuming it can?), they're not necessarily in order. Case in point:
Last_Name: JoinDate:
Smith          2/5/2010
Smuckers     1/10/2010An index range scan of 'S%' would return them in the above order, which is not ordered by joindate.
So is there any way I can refactor this (query or index) such that the index can be range scanned (using LIKE 'x%') and return rows in the correct order without performing a sort? Or is that simply not possible?Come on. Index column order does matter. "LIKE 'x%'" actually is full table scan. The db engine accesses contiguous index entries and then uses the ROWID values in the index to retrieve the table rows.

Using a ariable for an array name

I am currently working on the search method for my project.Which is to use breadth first search, to find the goal state of a problem.I am storing each new state encountered in a queue called states, and using an array for each state. So states would be a queue of arrays.
I was hoping to name each new state in order so state1 state2 state3 and so on. So for instance state1 would be an array containing the original board.
The problem I am having is declaring a new array for each new state. I was hoping to use a variable i to keep count of the number of states, so that when I declare a new array I could use something like
String[][] statei = original board array
So if i = 1 then state1 would contain a copy of the original array.
However I cannot seem to get java to recognise that i is a variable and not part of the name for the array.
Is there any way to let java know that I�m using i to represent a variable. Do I need to but i in quotation marks or something similar?
Thanks for any help

sorry i wasnt clear enough, what i have is an initial array called boards. Now every time i move a value in boards i need to create a new array. So for instance
i = no of states
new String [][] statei = a copy of boards[] with the affects of making the move
example if i was moving the value of boards[x][y] to boards[x][y+1]
i would need statei to be an array containg the change to the array above

Use of indexes

Hello
If I have a table that I'm adding a set of rows to that has an index on a couple of columns, and then within the same transaction re-query the table, can oracle use the index for the uncommited rows? I can see that there are reasons why it wouldn't be able to but then again I can also see reasons as to why it might be able to. Any help on this would be greatly appreciated.
David

Yes. The rows are already in the table and in the index, even if you have not COMMITTed them.

Using custom images for radiobuttons

Hi
I'm looking for help with creating a radio buttons with external images (fetched from XML/Javascript file) cause, I don't want to use standard looking radio buttons from components. I wish to use different images for each state of the button.
Any one can help me with some ideas how to change look of then radio buttons?

To manage homegrown radiobuttons as a group, you would incorporate an event listener function that manages the group. That function would know which radio button was selected via the event target and would act to reset all of the other radios while setting the one selected. I don't have a specific AS3 example, but below is a rough draft of the function/scenario. In this, I am using 3 radio buttons that have numerically differentiated instance names (rb1, rb2, rb3)...
var selectedRadio:MovieClip;
function manageRadios(evt:MouseEvent){
     // first reset all radios
     for(var i:uint = 1; i<4; i++){
          this["rb"+String(i)].gotoAndStop(1); // frame displaying deselected state
     selectedRadio = MovieClip(evt.currentTarget);
     selectedRadio.gotoAndStop(2);           // frame displaying selected state
     trace(selectedRadio.name);
rb1.addEventListener(MouseEvent.CLICK, manageRadios);
rb2.addEventListener(MouseEvent.CLICK, manageRadios);
rb3.addEventListener(MouseEvent.CLICK, manageRadios);
In this case, each radio button is simply a two framed movieclip, with stops for each frame... frame 1 displays the unselected state, and frame 2 displays the selected state.
For the code shown, I include an external variable (selectedRadio) that can be used to target information related to the selected Radio button. So if you assigned each radio with a variable (let's say you name it varName) that would hold data to be used in the processing elsewhere, you can get it using: selectedRadio.varName

Proper using of index for parallel statement execution

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