I am stuck with a query which is taking a lot of time to execute. Below is the pseudo code of the same:
SELECT TAB_ALIAS1.COL1,TAB_ALIAS1.COL2,TAB_ALIAS1.COL3
FROM TABLE1 TAB_ALIAS1
WHERE TAB_ALIAS1.COL4 = <INPUT PARAMETER1>
AND TRUNC(TAB_ALIAS1.ELAP_TIME) =
(
SELECT MAX(ELAP_TIME)
[code]....
We are using the below query to create a Materialized View but it has been running since 3 hours. It is an Oracle 9i database running in HP-UX.The quey is as follows,
(SELECT
/*+ use_nl(A) parallel (A,4)*/
A.ICD_CODE AS ICD_CODE,
A.ICD_DESC AS ICD_DESC,
A.PROC_GROUP as PROC_GROUP,
B.COMPL_ICD_CODE AS COMPL_ICD_CODE,
B.COMPL_GRP_TXT AS COMPL_GRP_TXT,
C.PROC_TYPE AS PROC_TYPE ,
[code]....
Name some database tool from which I can check the SQL Queries which my application is running.
NOTE: I do not want to check the queries which I am executing at the SQL command prompt but queries that are being run by my application at the backend.
In search queries generally we select 10-25 columns (more can't be displayed on the screen) from 5-10 tables
Say in case of insurance related application, the search might be on policy number, policy holder's first name, policy holder's last name, region, policy type etc.
And not to many columns we are displaying on the screen, say, 4 tables have collectively 4 * 20 = 80 columns, then we are displaying say 12-15 columns with 2-3 columns have aggregates on it.
since the search criteria (e.g. first name, last name, policy number etc.) is not known till last moment it will be a generic dynamic query
Is it possible that instead we create a Materialized view with query with only joining conditions but no filter conditions and selecting only columns to be displayed on the screen and then we will refresh the materialized view (to take care of recent business transactions) and fire refined query with filter criteria on this materialized view
Select col1,col2,col3,col4,col5
From tab1,tab2,tab3,tab4
Where tab1.col1=tab2.col1
And tab2.col2=tab3.col2
And tab2.col2=tab4.col2;
Will it improve performance of the search functionality
here we have an scenario where we want to find out all the sql statements that are executed in a particular time. The sql statements are executed via our application. I tried in awr report but it shows only the sql query which has taken long time to execute. and i even tried in V$session and V$sqlarea. how to view the executed sql statements in a particular session/current session
View 3 Replies View RelatedDoes parallel hint works in cursor queries? The cursor query is something like :
cursor c is
select /*+ parallel(s,8) */
from table ref_tab s ---- >>
<where condition>;
The table ref_tab hold data for a single day at any point of time and gets truncate before loading the next days data.On average the table holds around 7 million rows and doesn't contains any index (think that's fine as all together we are loading the whole set).And, we are using bulk logic with save exceptions to open the cursor and load the data into the target table.
I have few queries on PGA memory management.Since these queries are based on 2-3 examples not exactly same by nature I am summarising it after my understanding for the same
As I understand many workareas can be allocated to a single sql statement and number and sizes of theses workareas is controlled internally by Oracle when Automatic Memory management (PGA_aggregate_target and workarea_size_policy=Auto are set) Since many sessions share the PGA memory, the amount of memory available to each session may vary and if less amount of memory is available for a session for sorting then TEMP tablespace is used
[1] Can we say paging happens and can be checked at this time?
[2] Is there a difference in handling memory while populating pl/sql tables?
As I have encountered ora-04030 while some our developers were populating pl/sql tables but never encountered this error for sorting, hash joins etc Though I don't remember the width of pl/sql table, I am sure the developer used 'LIMIT' clause during bulk collect and still faced the issue.
With a single session on the server, I noticed that the difference in values displayed issuing 'free' command in linux and output values from sesstat did not match at all while there wasn't any heavy OS process involved during the period. I was expecting 'used' and 'free' values displayed by free command (linux) will change and difference would be approximately equals 'before and after values of session pga memory.
[3] Isn't it expected to match?
[4] Can we say in dedicated server, at any moment of time, the SUM of 'session pga memory' represents all the memory used by Oracle SGA, at that point of time?
select sum(value)/1024/1024 "memory in MB" from v$sesstat where statistic#=20;
During one of the tests I got following output (divide value by 10 for my visibility and avoid formatting)
SQL> select a.name, to_char(b.value/10, '999,999,999') value
from v$statname a, v$mystat b
where a.statistic# = b.statistic#
and a.name like '%ga memory%'; 2 3 4
[code]...
The above query is showing above values even when the pl/sql block execution is completed 30 minutes back
[5] Do we call this as 'memory leak' where memory is not released even while some time has passed since session has done something?Of course I am not checking at OS level as mentioned in question [3] above the values won't match!
Still the output of free command for reference(After the pl/sql block executed)
SQL> !free
total used free shared buffers cached
Mem: 3016796 2999660 17136 0 4308 1173260
-/+ buffers/cache: 1822092 1194704
Swap: 1048568 636124 412444
--(After the pl/sql block executed)
SQL> select * from v$pgastat;
NAMEVALUEUNIT
aggregate PGA target parameter 524288000bytes
aggregate PGA auto target 456256512bytes
global memory bound 26214400bytes
total PGA inuse 17328128bytes
[code]...
[6] What could be the significance of negative values of 'session pga memory/max'?
Last We have an OLTP system and in the night we run batch processes in 2-4 sessions
Suppose I have 10 GB RAM and with PGA setting of 3.5 GB Now I want the batch process sessions to use max possible memory during nighttime and toggle the setting back in the morning
[7] With above settings (10 GB RAM and 3.5 GB PGA) how can I divide the memory among 4 sessions?
Shall I set 1) PGA_aggregate_target=0 2)Workarea_size_policy=manual 3) Sort_are_size 4) Hash_area_size
[8] What would be approx values for parameter 3 and 4? will it be straight 3.5 GB/ 4?
We have a big hierarchical query which is now running for a long time (around 6 hours. earlier it was running for 3 hours). We have to tune this query so that we run the jobs within a stipulated time frame.
The query below inserts around 42 million records in to the table WK_ACCT_WSTORE. I have attached in the text file.
I am using Release 11.2.0.3.0 - 64bit Production version of oracle. Now we are having 3-tier architecture, (firewal/web/app/DB).Now i saw , some of the 'sql' queries, running till ~10hrs in my database and those are part of application(module JDBC THIN CLIENT). After had a talk java guys, they ask to kill the sessions specific to those queries. They are part of search TO, in which user put some large values for the date range and went to other TAB, but these queries gets running infinitely in the database, and user is not interested in the result set.
So how to avoid these things, as because in past, our database has suffered resource contention leading to application slowness. So i was planing to set different timeouts using 'database resource consumer group' for online user request and batch request depending on the app server(that is by machine names) request.
So i have done below set up in my local to test one scenario, in which i will try give a database call from difference machine, and it should get timeout after the specified duration. But its not working , as expected. The calls from the specified machine are not getting assigned to the created 'Consumer group'.
Begin
-- create the pending area
dbms_resource_manager.create_pending_area();
END;
/
BEGIN
-- Create the consumer group
[code]....
After this when i am verifying calls from machine, 'LR9XY7T8' they are belongs to the consumer group 'OTHER_GROUPS' and sql query not getting timed out within 60 seconds as mentioned.
I have a table with:
1 million rows
average row length 200 bytes
50 columns
and this update statement
UPDATE mytable SET varchar2_4000_column = replace(replace(replace...300 times)
It looks at every row in the table (no WHERE clause) and does these 300 replace operations on this column for each row. Each replace replaces with a null so effectively it is removing strings. Much of the time these strings are not in the column.
This update statement takes 25 minutes and it is 98% CPU and 2% USER_IO time.
I figure that is what is taking all the time since it is a CPU bound statement. if rows in this table are persistent over time then tag rows with a flag to show which ones have already been processed and skip these next time around.
I have a table which has 4M records
This table has a query where one of the condition is
AND STATUS <> 'C'
Now the data is as following
select count(*) record_count, status from new_business group by status;
record_countstatus
4298025C
15N
13Q
122S
I want to know if following index would be useful in this case while the condition in where clause is
"AND STATUS <> 'C'"
create index nb_index_1 on new_business(case when status in('N','Q','S') then 1 else NULL end);
Or
create index nb_index_1 on new_business(case when status ='N' then 'N' when status='Q' then 'Q' when status='S' then 'S' else NULL end);
I tried it on a sample table but the index is simply not picked up even when hinted following are the db level settings
query_rewrite_enabled string TRUE
query_rewrite_integrity string enforced
I tried it 'query_rewrite_integrity' with 'trusted' as well .
determine if a function is worth pinning in memory? I want to come up with a percentage, implying that if the function is already im memory 80%+ of the time then it is not worth it.
View 5 Replies View Relatedwhen am trying to use nvl for one condition it is taking lot of time to execute but when am removing nvl function then the query executing in 2 min. condition is given below
(HOI2.ORG_INFORMATION1)=nvl(TO_CHAR(:p_set_of_books_id) , HOI2.ORG_INFORMATION1)
but when am using the same condition as below the querry executing in 2 min
(HOI2.ORG_INFORMATION1)=TO_CHAR(:p_set_of_books_id)
my query given below
(SELECT cust.customer_number cust_no, cust.customer_name customer,
cnv.item_no, SUM(wd.shipped_quantity) shp_qty_nos,
0 rtn_qty_nos,
ROUND(SUM(cnv.cnf * wd.shipped_quantity), 3) shp_qty_tons,
0 rtn_qty_tons, 0 net_shp_qty_nos, 0 net_shp_qty_tons
[code]...
I have created below function to remove specific words/special characters from string. This function is producing expected result. Using this function i need to insert around 900000 records in name_compress table. Insert is taking around 7 mins, how we can tune this function so that insert will be executed within 1-2 mins.
Function -
CREATE OR REPLACE FUNCTION NAME_FN(IN_STRING1 VARCHAR2)
RETURN VARCHAR2 IS
V_OUTPUT VARCHAR2(300);
V_OUTPUT1 VARCHAR2(300);
V_OUTPUT2 VARCHAR2(300);
V_OUTPUT3 VARCHAR2(300);
[code]...
I have performance problem with 7 queries involving groupby clauses in OLAP database.These are queries triggered during siebel DAC run
kumar[size="4"][/size][color="#0000FF"][/color]kumardba
Looking to understand the difference between instance tuning and database tuning.
What is the difference between these two tuning exercises? I understand that an instance is memory based structures (logical) where as database consists of physical structures.
However, how does one tune a database the physical structure? Does it have to do with file placements/block sizes etc. Would you agree that a lot of that is taken care by ASM now in 11g? What tools are required/available (third party as well as oracle supplied) for these types of tuning scenarios?
It seems certain queries search by the number of days to ship(number of days between the order and shipping dates). What kind of index would improve the performance of these queries?
View 2 Replies View RelatedUsing rownum in PL/SQL can significantly reduce performance and throughput of queries.
For example,
CODEselect *
from (select ...
from ...
join ... on ...
join ... on ...
left join ... on ...
where ...
group by ...)
where rownum < 500
takes much more time on a heavy loaded db than
CODEselect Y.*
from (
select X.*, rank() over(order by ...) rnk
from (select ...
from ...
join ... on ...
join ... on ...
left join ... on ...
where ...
group by ...) X) Y
where rnk < 500
I suspect it's because Oracle optimizer goals all_rows and first_rows.
Can we call a function in IN of "WHERE" clause.I mean to say like:
Select *
FROM table1,table2
WHERE table1.col=table2.col and CONDITION IN FUNCTION1
How to call outside function in procedure
View 11 Replies View RelatedI want to have something like this:Run PL/SQL function and in middle of function call JAVA function and when JAVA function is done continue PL/SQL function.
Because I have PL/SQL function who inserts into table information.And the JAVA function is uploading/streaming file to column->blob.And in the end of PL/SQL function goes insert into table with file extension and check for *.edoc validation.I can't do it with PL/SQL only. how to do this right or how to run JAVA function in PL/SQL.
I am defining a function in a schema as a user with admin role (default). The function is to do a call to another function on a custom package in SYS schema.
something funny happens : when I compile the function (defined with authid as DEFINER)it says that the function SYS.custom_package.myFunction is not defined.
however if I do a select sys.custom_package.my Function from dual it's okay.
why this behaviour and how to work around it? You see, the package in SYS proposes a number of other functions that I don't want to expose. I only intend to create some sort of wrapper function that would Marshall the call to the my Function only on the custom_package in SYS.
my wrapper function looks something like that :
create or replace function myFunction_wrapper authid definer return pls_integer is
begin
return sys.custom_package.myFunction;
end;
i am trying to call a function from Sql statement and i am getting this error ORA-06572: Function XX has out arguments.
View 2 Replies View RelatedI have two tables with 113M records in DWH_BILL_DET & 103M in prd_rerate_chg_que and Im running following merge query, which is running for 13 hrs to update records, which is quiet longer time.
SQL> explain plan for MERGE /*+ parallel (rq, 16) */
INTO DWH_BILL_DET rq
USING (SELECT rated_que_rowid,
detail_rerate_flag_code,
rerate_sel_key,
[code].....
I have a package includes 22 functions, each function just returns a sql template (clob type).
I also have a stored procedure called query_builder, query_builder has applicationName and statementName as parameters. I need to call these functions in the package based on the given applicationname and statementname.
CREATE OR REPLACE PROCEDURE Query_builder (ApplicationName varchar2, StatementName varchar2) IS
SQLSkeleton varchar2;
BEGIN
PackageName := ApplicationName||'_SKELETON;
SQLSkeleton := PackageName.StatementName; -- I know this will not work, but how can i call these function dynamically?
Can we call a function within decode statement. I am able to do the same for simple example function . But In my actual procedure it's giving the error message . Are there any restrictions to call function with in decode statement?
View 4 Replies View RelatedI would like to know if using varchar parameter in sql queries with number column can result in performance degrade.
Ex: Procedure testa ( myparam varchar) is
begin
select col1 into var1 from table where colno = myparam;
end;
Here col no is a number column and myparam is varchar. I feel its better to change the parameter to number.
How the length of column width effects index performance?
For example if i had IOT table emp_iot with columns:
(id number,
job varchar2(20),
time date,
plan number)
Table key consist of(id, job, time)
Column JOB has fixed list of distinct values ('ANALYST', 'NIGHT_WORKED', etc...).
What performance increase i could expect if in column "job" i would store not names but concrete numbers identifying job names.
For e.g. i would store "1" instead 'ANALYST' and "2" instead 'NIGHT_WORKED'.
I have a question about database fragmentation.I know that fragmentation can reduce performance in query times. The blocks are distributed in many extents and scans process takes a long time. Oracle engine have to locate the address of the next extent..
I want to know if there is any system view in which you can check if your table or index has high fragmentation. If it's needed I will have to re-create, move or rebulid the table or index, but before I want to know if the degree of fragmentation is high.
Any useful script or query to do this, any interesting oracle system view?
I made this script but I still don't quite understand if the syntax is correct. I just wanted to create a function and call it in an anonymous block. I then wanted it to use a variable as a parameter in an iteration and output the variable every iteration. It's done basically but I know it's not 100% right. The fibonacci function looks like its going to loop an infinite number of times if the parameter is greater than 2.
CREATE OR REPLACE PACKAGE myPACKAGE AS
CREATE OR REPLACE FUNCTION fibonacci
(n BINARY_DOUBLE) RETURN BINARY_DOUBLE IS
BEGIN
IF n <= 2 THEN
RETURN 1;
[code]........