Performance Tuning :: Retrieving From Data Is Slow
Jan 12, 2011I'm extracting/retrieving the data from the oracle database using Java application it's bit slow. However, when I retrieve from the SQL server it's faster than oracle.
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Performance Tuning :: Delete Is Very Slow
Apr 26, 2013I am running one simple delete statement in one table with rownum<10000 but it is taking nearly 10 to 15 mins.Table doesn't have any child table rows and triggers.
View 13 Replies View RelatedPerformance Tuning :: (Fast Refresh) MV Too Slow?
Sep 23, 2010We have a MV which fetches data from around 27 tables containing 26 joins out of which 25 are outer joins. Some tables in the query are being referred multiple times through different alias names and hence the actual no of physical tables used is 18. This MV takes about 50 mins to refresh through complete refresh mechanism. We decided to make it fast refresh and thus made these configurations:
- Created MV logs based on rowid for each of the base tables.
- Recreated MV using FAST refresh,with primary key option enabled
- Pulled rowid for all these tables in the select column statement.
Even after making all the recommendations suggested by Oracle for fast refresh MV's we are still getting refresh time of around 65 mins(refresh time increased!!!).We already have indexes built on all the join columns of the base tables. What else do we need to do to make this a "fast" refresh MV ?
Performance Tuning :: Application Slow In EE But Fast In XE
May 22, 2012My ERP Application is responding fast while running reports or saving entries, if Oracle 10g Express Edition (XE) is installed. But in Oracle 10g Enterprise Edition or Standard Editions the same application is running very slow.
View 1 Replies View RelatedPerformance Tuning :: DML Slow When Table Have Many Rows
Sep 4, 2011If a table(have a primary key) is empty(after truncate),the sql of dml(insert,update) is very quickly,but if the table have many rows about 10,000,000 rows, the dml is very slowly,why?
View 6 Replies View RelatedPerformance Tuning :: Database Is Slow On Insert
Mar 23, 2012we are using oracle 9i on AIX Server. When Customer were accessing the database, accidentally power was shut down. we restarted the Server,and Oracle database. all resumed successfully.
However while doing "Payments by the customer" it takes a lot of time to insert even a single payment record on database.The database is Live and our customer are very much frustrated,
Performance Tuning :: Slow Join Between Dba_tab_cols And Dba_types
Nov 14, 2012The product I work on requires a query to tell us what tables are dependent on certain types.
SELECT dba_tab_cols.owner,
dba_tab_cols.table_name,
dba_tab_cols.data_type_owner,
dba_tab_cols.data_type
FROM dba_tab_cols
JOIN dba_types
ON dba_types.owner = dba_tab_cols.data_type_owner
AND dba_types.type_name = dba_tab_cols.data_type
WHERE (dba_types.owner IN ('SCHEMA1', 'SCHEMA2'......))
I find this query to be pretty slow. I think it is because data_type_owner in dba_tab_cols is not indexed. Adding an index is not an option because users expect our product to read-only.
Performance Tuning :: DB Import Too Slow After Server Reboot
Jul 4, 2011Few days ago, My database server no access to StorageBox then I reboot it then after works fine. But, know DB import process is too slow. Before 100GB DB import process completed within 10 hours when server normal running. Now 2 day working, but not complete
How to investigate this issue? Maybe I miss increase some parameters on the Server or Oracle?
Here is my server brief info:
RAM is 16GB,
SWAP size is 16GB,
CPU 12 cores
SQL> show sga;
Total System Global Area 4294967296 bytes
Fixed Size 1984144 bytes
Variable Size 369105264 bytes
Database Buffers 3909091328 bytes
Redo Buffers 14786560 bytes
Performance Tuning :: Oracle (HP-UX) Connection Very Slow From Windows Client?
Jun 18, 2012I have an Oracle database (9.2.0.7) installed on a HP-UX server.When trying to access this database from another HP-UX or Linux server, connection is fine. But when trying to connect from a Windows based client, connection is very slow (almost 1 minute to return the result of a 'select count(*)' like query, which is immediate from the Linux client).
Here are some facts I can add :
- Clients and servers are on the same network segment (it is not a network matter)
- No matter which client version I use, there no difference
- I tried to know what happens on the Oracle server when performing my sample query using tusc command : the result is that the server is performing exactly the same actions when sending my query from a Linux client or a Windows client
- The only relevant difference seems to be the client OS
Performance Tuning :: HIBERNATE Query Runs Slow But Ok In SQLPLUS
Sep 14, 2012I have a query which takes 5 minutes when run through the java app which uses hibernate. I've cut and pasted the SQL directly from hiberate trace file and run it in sqlplus/sqldeveloper and it runs instantly (0.01 seconds)(uses the index all ok and explain plan looks good - see below.) I don't know how to get the explain plan when it's running through the app or why it should be any different anyway as the query is identical.
My query is as follows:
SELECT /*+ INDEX (SPD SPD_SEQ_CODE) */ SPD.*
FROM SEQ_ADDR_DATA SPD, SEQ_ADDR_LEVELS SPL
WHERE SPD.SPVR_ID = '10'
AND SPL.SPLE_ID = SPD.SPLE_ID
AND SPL.SPLE_LEVEL <= '2' AND SPDA_ID NOT IN
[code]....
Performance Very Slow Inserting Data Into Table
Jun 25, 2013I am trying to insert huge data into another huge table which is almost taking around 2-3 hrs. See my below query
INSERT /*+ APPEND *//*+ NOLOGGING */ INTO DB1.Table1 SELECT * FROM DB2.Table2 ;
COMMIT;
Both Table1 and Table2 have same structure and table1 is master table having 100 Billion records and table2 having 30 Million records. This is a direct insert where each day this operation carried.
Performance Tuning :: Same Data But Different Performance Results
Sep 3, 2010what the principal things to look at when we have for the same query different performance results are?I have 2 different bases: the plan and data are the same but performance results are very differents.
View 10 Replies View RelatedPerformance Tuning :: Split Data Separated By Comma / Then Create Collection With Data Mapped From Other Columns
Sep 25, 2013DB Used : Oracle 10g.
A table X : NUM, INST are column names
NUM ----- INST
1234 ----- 23,22,21,78
2235 ----- 20,7,2,1
1298 ----- 23,22,21,65,98
9087 ----- 20,7,2,1
-- Based upon requirement :
1) Split values from "INST" Column : suppose 23
2) Find all values from "NUM" column for above splitted value i.e 23 ,
Eg:
For Inst : 23 ,
It's corresponding "NUM" values are : 1234,1298
3) Save these values into
A table Y : INST, NUM are column names.
INST NUM
23 1234,1298
1) I have a thousand records in Table X , and for all of those records i need to split and save data into Table Y.Hence, I need to do this task with best possible performance.
2) After this whenever a new data comes in Table X, above 'split & save' operation should automatically be called and append corresponding data wherever possible..
Performance Tuning :: Get AWR Report Data?
Aug 8, 2012I am having only select_catalog_role in database. Can I take complete AWR report data from awr views without using DBMS_WORKLOAD_REPOSITORY package?
View 6 Replies View RelatedPerformance Tuning :: Data Caching
Feb 7, 2011sometimes when I re-run a query a few times, the speed after the first run become much faster. this is a problem for me when I'm trying to optimize a query. is there some sort of cache? can it be disabled?
View 7 Replies View RelatedPerformance Tuning :: Inserting Data Using FOR ALL
Mar 6, 2011CREATE OR REPLACE procedure fast_proc (p_rows out number)
is
TYPE object_id_tab IS TABLE OF all_objects.object_name%TYPE INDEX BY BINARY_INTEGER
lt_object_id object_id_tab;
CURSOR c IS
[Code]....
Warning: Procedure created with compilation errors.
Errors for PROCEDURE FAST_PROC:
LINE/COL ERROR
-------- ---------------------------------------------------------
13/7 PL/SQL: SQL Statement ignored
13/22 PL/SQL: ORA-03001: unimplemented feature
I am not able to do INSERT but I am able to do UPDATE/DELETE? What is this inbuilt functionality?
Performance Tuning :: Big Table Data Maintenance
Jun 17, 2011We have few tables in our production database which are havoc in size and will increase in size in future too so as part of the corrective measures , we have jotted down the below 3 methods to manage the size of those tables :-
1> Partitioning the table and take the export of identified partitions and after that, truncate those partition.
2> Creating history tables and remove not so current data from the original table to history table.
Performance Tuning :: Oracle Data Migration
Jun 7, 2011We have a data migration scripts written for oracle. Data is not huge but we are observing that the migration is faster in the development labs but is 5x slower in the production site.
The development Oracle setup is on Windows and Production setup on Solaris. I have attached the AWR generated for a period where migration was run for 3 hours and stopped due to slow performance.
Here is my initial analysis.
1) The first timed events is the DB CPU. Hence I feel the migration scripts can be modified to run in parallel so that they can finish faster. However here the question arises why it should run faster in development env if this is an issue.
2) I tried increasing the
a.large_pool_size set to 512M
b.sga_max_size set to 8G
c.sga_target set to 8G
from 0, 4G and 4G respectively.
I have attached the AWR and below are the etc/system contents for solaris settings.
* Begin MDD root info (do not edit)
rootdev:/pseudo/md@0:0,1,blk
* End MDD root info (do not edit)
set noexec_user_stack=1
set noexec_user_stack_log=1
* IBMdpo vpath_START (do not remove)
* default SCSI timeout is 60 seconds
* uncomment to change SCSI timeout * set sd:sd_io_time=0x1e
forceload: drv/vpathdd
* IBMdpo vpath_END (do not remove)
set noexec_user_stack=1
set semsys:seminfo_semmni=100
set semsys:seminfo_semmns=1024
set semsys:seminfo_semmsl=256
set semsys:seminfo_semvmx=32767
set shmsys:shminfo_shmmax=4294967295
set shmsys:shminfo_shmmin=1
set shmsys:shminfo_shmmni=100
set shmsys:shminfo_shmseg=10
P.S. The awr report is renamed to .txt from .html to be able to upload the file.
Performance Tuning :: Table Rebuild Should Be Done After Removing Most Of Its Data?
Oct 23, 2012We are on Oracle 10.2.0.4 on Solaris 10. There is a table in my production db that has 872944 number of rows. Most of its data is now unnecessary, we need to retain, based on a date column in the table just last one month's data and delete rest of the data. So after that the table will have just 3000 rows.
However as the table was huge earlier(872k rows prior to delete) , does the delete of data release its oracle blocks and does the size of the table reduce? If not, will it rebuild the table online (online redefinition) so that the query that does a full scan on this table goes faster?
I checked using an example table that just delete of data does not remove the oracle blocks - they remain in the user_tables for that table and cost of full table scan remains same. We have a query that does the full table scan so I am thinking that after this delete I should do an online table re-definition , is that the right decision?
Performance Tuning :: Which Index Will Be Better For Fast Retrieval Of Data
Nov 12, 2010I create a view on production server which takes almost 10 to 12 minutes when it shows data. this view contains 3 or 4 tables on which all primary and unique columns have indexes.which index will be better for fast retrieval of data .
View 5 Replies View RelatedPerformance Tuning :: Lot Of Time Being Taken To Delete Data From A Table
Apr 27, 2012I have a table which contains 8,21,177 amount of data totally.Now I am trying to delete around 4,84,000 of data from this table by using just one filter i.e. my query is something like below
DELETE /*+ parallel(resource,4) */ FROM resource where created_by = 'MIGN'
This is going to delete 4,84,000 rows of data . But my current issue is this is taking lots of time to delete the data . To be precise , its almost taking 25 hours to delete this data..The created_by column is indexed .
Execution Plan
----------------------------------------------------------
Plan hash value: 2389236532
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time
|
--------------------------------------------------------------------------------
| 0 | DELETE STATEMENT | | 499 | 20459 | 39 (0)| 00:00:
01 |
| 1 | DELETE | RESOURCE | | | |
[code]....
Performance Tuning :: Copy Data From Transaction (DB1) To Reporting (DB2)
Nov 26, 2010We are copying our transaction tables data into another database for our reporting applications (say every day midnight refresh will happen).
The Transaction Database has some 30tables. Existing system is following below points and it is taking 2hours to complete.
1) Truncate data from reporting database (or schema)
2) Direct path Insert into reporting database (or schema) as select * from transaction tables.
3) Rebuild index and Enable constraints.
Note: Each tables data will vary from 30lakhs to 50lakhs. Dump/import/export is not advised by the client.
I want to cut down the time i.e., below 2hours. Instead of above method. Can go for a field in each table specifying the time of each records update/insert operation and then pick the modified records only and copy into reporting db.
Performance Tuning :: Insert Data Fast On Table
Oct 15, 2013I am inserting data using a procedure for 2012 and 2013 year which is using partitioned tables includes crore of data in a partition taking lot of time or taking months. Is there any other way by which I can insert data fast from our query.
View 14 Replies View RelatedPerformance Tuning :: How To Refresh Materialized View Data
Jun 12, 2013I have created a materialized view and also a normal View, which has 3 tables used in both the views, when inserted new records it reflects in a normal view but when i select the materialized view i cant see the updated data.
here is the materialized view i created;
CREATE MATERIALIZED VIEW pct_sales_materialized
BUILD IMMEDIATE REFRESH ON DEMAND
ENABLE QUERY REWRITE
AS
SELECT A.DEP_NAME,B.EMP_ID,C.EMP_NAME
FROM department_head A,department_child B,emp_detail C
WHERE A.DEP_ID = B.DEP_ID
AND B.EMP_ID = C.EMP_ID
Performance Tuning :: Options For Querying On The Skewed Data
Feb 10, 2012We have a table with huge data which is skewed on a 'status' column. The 'status' column has 6 distinct values with 1 particular value occupying 80-85% records.
In the batch process we query the data on the status and process the retrieved records. My senior is insisting on partitioning which I see not much feasible considering cost implications just for a part of functionality
See there are 6 status 'A','B','C','D','E','F'
with 'A' occupying 80% records
'B' to 'F' occupies 2% till 14% records in the table(approx)
1) Create a conditional index on status (using case) to have records with all statuses except 'A' Then create If-ELSE structure
IF input parameter is 'A'
select /*+ FULL Parallel(t) */ * from t where status='A';
ELSE
Select /*+ INDEX (t conditional_index) */ * from t where status in ('B','C');
END IF;
I want to create conditional index here for 2 reasons
1] since it will have values for status except 'A' this nullify the chance that this index will be picked up when status='A' will be queried
Thus making the performance worst (status ='A' is for 80% records) - The IF-ELSE is additional protection
2] Less impact on the DMLS as the index will not be on status='A' which contribute to large chunk of records
2)Populate a dummy table which would contain rowid and status. Since the business closes at 21:00 and batch process starts at 21:30
Between these times periods refresh the dummy table every day using merge (to catch business transactions during the day)
Now during the batch process retrieve records from the main table using the rowids in the dummy table depending on the input status value
3)Create index on status
Make sure hard coded status values are used in the database procedures
Gather stats with the histograms
And leave it to the Optimizer to choose the best possible path
Performance Tuning :: Data Type Conversion Impact?
Nov 28, 2011my sql query has three tables in from clause so it has two join conditions and one where condition.
account_no is number data type and v_account_no is varchar2() data type
The where clause is :
"where account_no=to_number(v_account_no)" with this condition in my sql query has the cost 392
we just modify the where clause as where v_account_no=to_char(account_no) with this condition in the sql query has the cost 11.
what is impact of this data type conversion and difference between these two "to_number() and to_char()" in performance wise to reduce the cost of query?
Performance Tuning :: Used Same Dmp File To Restore Data And Settings
Oct 15, 2013I am getting back into Oracle (from a long haul in MS only env.) and am now testing Oracle installs.I have been given a task of seeing the diff. between 12c and 10.2g...I set up 2 vms (excatly same configs) and used the same dmp file (on both env.) to restore data and settings for our jobs to run.We have some aggregated data, and cubes with DIM tables each being run on the vm machines. We run nightly jobs to rebuild our cubes.
I am supposed to see/analyze the value of 12c, and understand things might vary from company to company, but am perplexed at my result.12c is half the speed of 10.2g, both env. are the same out of the box with same dmp file and same hardware.
I am using the same dmp file, with the same jobs on each machine, with both vms having 10.2g or 12c installed out of the box as is.what default oracle settings might have changed from 10.2g to 12c that could make the exact same env. run twice as slow on the 12c?
Expectations were that out of the box with both machines running same jobs on same data (from dmp files) would have it that 10.2g would be slower than the 12c, except the 12c takes 2 times as long to run the jobs. I have reviewed every possibility as I know usually the problem is the person sitting in the chair and not the pc...but I confirmed all was identical from the one vm env. to the other, except the version of oracle out of the box.
What could be done to bring that default setting back to atleast equal time between the 2, that would give me a great starting point. Otherwise, I would have to toss this up to bloatware.
I read up a bit on the CBO, and know this might have changed in 12c.is there a way to bring it back to a backwards ealier config, so as to atleast match both env. execution plans?
Performance Tuning :: Data Dictionary Cache - Dc_objects
Jul 4, 2011In order to improve the performance of our live server, I am trying to do an exhaustive comparison with our test environment which is quite quick in spite of the fact that we port the data from Live every month.
There are no obviously slow queries appearing in the the top SQLs of AWR, we have optimised such things already. Right now it is about general uplift rather than SQL based tuning.
I picked up random SQLs and I noticed a marked differences in the execution time. Typically they are 3 to 4 times and there are cases much more than that.
1. I observed that, while the explain plan of the queries are same, trace of the queries give a different picture. I have observed that the recursive calls, consistent gets and sorts(memory) are quite high on Live.
2. I have no solid reasons to say this but my instincts tell me that the recursive calls is the major contributing factor. It is sometimes 2000+ for an SQL.
3. On googling more on that, it finally made me compare the data dictionary on the AWR report of test and Live.
The dc_objects caught my eyes. In that 4 hour AWR, there were about 10 million get requests and the pct miss was ~10. For similar load, the test server had 5 million gets with 0.08 PCT miss for 4 hours.
Slow Performance On New 11gr2 Linux DB?
Aug 27, 2013we are busy updating one databasee from a windows platform 2003 oracle 10G to a linux and oracle 11r2
We exported/imported the data and it looks ok Explain plans look the same . but our heavy batches are twice slower than on the windows box ,the two top events are disk related, sequential and scattered reads there are 90% of the time of the batch job , i read some white paper and found that using ASM can be bad in some cases the same with the linux for this particular kind of scattered reads , i was just wondering if just changing the SGA to 10GB instead of 4GB to get more cache and speedup the things .
Performance Tuning :: Database Links - Display Consolidated Data?
Oct 14, 2013A website requires to display consolidated data from databases located in different geographical regions (India, London and New York). The application server for the website is hosted only in one location India. What are the techniques that can be used for faster retrieval of data from all 3 databases?
Note: There is no need of real time data retrieval from different regions; however the user should able to view the updated data at predefined intervals.