I 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.
I have procedure that is used by trigger but I define it as Varchar2 it's result show number.
change my PLSQL to use as varchar,
If trigger fired, the procedure make this query
select CB_SMS_FLAG, CB_SMS_DT from TM_SFS_CUST_04 where CUST_NUM = 01071234151;
but I want this query
select CB_SMS_FLAG, CB_SMS_DT from TM_SFS_CUST_04 where CUST_NUM ='01071234151';
because CUST_NUM is VARCHAR2(12)
so it can use index appropriately.
how can I change my PLSQL this sentence,
v_sel_sql1 := 'select CB_SMS_FLAG, CB_SMS_DT from ' || pTBL_NM ||' where CUST_NUM = ' || pCUST_NUM;
Here my code
CREATE OR REPLACE PROCEDURE ORAASFS.P_TM_SFS_CB_SMS_CNT_upd_104(
gKIND VARCHAR2,
pCUST_NUM VARCHAR2,
pSMS_CNT NUMBER,
pSMS_CLC VARCHAR2,
pRD_FLAG VARCHAR2,
[Code]....
I am working on Oracle 10g and Below is my query which is taking 30min. to execute. I am using two inline view and then make joins on these inline view because of i think it Degrade Performance.
Query :-
SELECT LEVEL_USER,
TRIAL_NO,
UNIT_NO,
COUNTRY_CODE,
PERSONNEL_NO,
[code].......
Note :- i have Attached the explain Plan for the same .Please let me know how can i improve performance of this Query.
How can i join two quires together to get result.
My requirement is:
First i want to select Table as we do
Select * from tab;
Then i want to describe the table as we do
Desc WO;
How can we join these two queries to have result.
I am trying to display the results from 2 queries, one is supposed to display the count of the employees, per department, who win over the average of the entire company and the other one is supposed to display the count of the employees, per department, who win under the average of the entire company.
I used a UNION ALL, but all it does is merge the results from the ones that win over and under the average into one row, is there a way to separate them? I tried assigning names to each salary using AS but it only displays the first I put in.
sql
Original
- sql Code
(
SELECT DE.DEPARTMENT_NAME, COUNT (EM.EMPLOYEE_ID) AS MAYORES
FROM DEPARTMENTS DE, EMPLOYEES EM
WHERE DE.DEPARTMENT_ID = EM.DEPARTMENT_ID
AND EM.SALARY > (SELECT AVG(EM.SALARY) FROM EMPLOYEES EM)
GROUP BY DE.DEPARTMENT_NAME
[code].....
When we are running a query it is giving us the result based on the conditions .But to know what exactly is happening in the database when we are running a query against it and how finally it returns the result.
View 1 Replies View Related I see you can build an address object consisting of street name and number, city and so on, and use this in CREATE TABLE, so all tables use the same fields for addresses. And moreover you can add check functions to prevent street numbers to be negative for instance in the constructor. You can even use inheritance. I like that.
However, all teaching on this subject I found on the Internet starts with structs (points consisting of x and y, persons consisting of name and address, etc.). Then they go to inheritance and show how to build an employee who is just a person plus an employee number. They never start with simple types.
What I would like to do would be rather to start with basic types such as number or varchar2 and inherit from them. An EAN is a VARCHAR2 holding only digits where the last digit is a check sum that must be matched. An item number may be a VARCHAR2 matching 'NNN-AAAA'. A simple string may be a VARCHAR2 where no functional characters such as carriage return, etc. occur.
I would then write my create table statement thus:
CREATE TABLE item (itemno T_ITEMNO, ean T_EAN, itemname T_SIMPLESTRING); and inserts like INSERT INTO item values('123--BCD', '1234567890abc', 'toy') would fail with exceptions like 'item numbers must be formatted NNN-AAAA' or '1234567890abc is not a valid EAN'.
However this seems not possible:
create or replace type T_EAN under varchar2
(
constructor function T_EAN(p_string in varchar2) return self as result
);
fails with "PLS-00580: supertype must be an object type".
Rather than creating completely new types, I would start with extending existing types, but this seems not possible. Is that really impossible or am I using the wrong approach?
Today we faced one strange issue Varchar doesnot print the zero front of number
eg
SQL> select agent_code from table_name where AGENT_CODE = 0061;
AGENT_CODE
----------
61
61
where in my database agent_code columns as value 0061 and 061 for both it shows same value.
Following are 2 queries, which return same results as far as the input parameter is NOT NULL
select /*+ gather_plan_statistics */ * from PX_CJQ where decode(:x,null,1,object_id) = NVL(:x,object_id);
select /*+ gather_plan_statistics */ * from PX_CJQ where object_id = NVL(:x,object_id);
However the execution plan differs a lot The FTS cost or rows accessed count also varies what could be the reason? The PX_CJQ is simply select * from dba_objects and has index on object_id which anyway is not being used in this case
variable x number
exec :x:= 28
Query - 1
***************
***************
SQL> >select /*+ gather_plan_statistics */ * from PX_CJQ where decode(:x,null,1,object_id) = NVL(:x,object_id);
SQL> >select * from table(dbms_xplan.display_cursor(NULL,NULL,'ALLSTATS LAST'));
[code]...
Query - 2
***************
***************
SQL> >select /*+ gather_plan_statistics */ * from PX_CJQ where object_id = NVL(:x,object_id);
SQL> >select * from table(dbms_xplan.display_cursor(NULL,NULL,'ALLSTATS LAST'));
PLAN_TABLE_OUTPUT
[code]...
29 rows selected.
SQL> >
I have three select queries. Each of them returns a single column. I want the result of these queries into a single table..
I tried this way..
select * from
(first select),(second select),(third select);
this gives duplicate rows...
Have table with two columns with datatypes as number and varchar and the values in A column like 1,2,3 AND B column values like a,b,c. Now need to display data in a single column as 1,a,2,b,3,c.
View 4 Replies View RelatedI've a large table on which I applying aggregate and group by functions to the the results.
Here are two of the columns in my table:
Name ==== Score
John ==== 200*
Zohaib ==== 299
Ali ==== 0*
John ==== 200
Maria ==== 150*
Ali ==== 0
Maria ==== absent
John ==== absent
Here astrick (*) means with distinction....
The "score" column is a varchar column I want to run a query on this table to show the highest score for each student and the output should be like this:
Name ==== Score
Zohaib ==== 299
John ==== 200*
Maria ==== 150*
Ali ==== 0*
Important note:
1. if there is a tie between two highest scores like for a student, incase of john 200 was made twice, but the score with asterick (*) will be the "maximum" becuase it is with distinction so the output should also show the the highest score with asterick.
2. the output should show the the 2nd column (score) in desc order of highest score by each student...again incase of a tie, the one with astrick will come first in the result..
I know with just mere numbers, that is pretty easy but in this case it is a varchar column and also i need the astrick along with the highest score.
I want the simplest and shortest query if possible to achieve this result
I hope I've been able to clearly explain my requirment. I am using 10G.
I have a table and data like mentioned below.
create table emp( ename varchar2(20));
insert into emp values ('122');
insert into emp values ('abc');
insert into emp values ('0.2');
insert into emp values ('0-5');
insert into emp values ('25-30');
SQL> Select * from emp;
| ENAME |
-------------------
| 122 |
| abc |
| 0.2 |
| 0-5 |
| 25-30 |
I am running the code
SQL>select regexp_substr(ename , '^[[:digit:]]+.[[:digit:]]+$|^[[:digit:]]+$')
from emp;
AFTER RUNNING I AM GETTING THIS
| REGEXP_SUBSTR(ENAME,'^[[:DIGIT:]]+.[[:DIGIT:]]+$|^[[:DIGIT:]]+$') |
---------------------------------------------------------------------
| 122 |
| (null) |
| 0.2 |
| 0-5 |
| 25-30 |
| (null) |
Why it's not excluding '0-5' and '25-30', how I should write code to exclude this and Is there is any function in oracle to check for numeric in column and print.
select numeric values from a varchar column
For Example:
select * from t1 ;
ID
----------
00300
ABCXY
04230
xyzab
i need to fetch only numeric values from column id
My output should be
00300
04230
how to convert existing table with varchar column to a clob
View 1 Replies View RelatedI need to order the result set with different data types based on the input parameter.
select * from scott.emp sc order by decode('&input_parameter',1,sc.empno,2, sc.ename);
If the input_parameter is equals to 1 then,ordering should be based on EMPNO which is Number data type.
If the input_parameter is equals to 2 then,ordering should be based on ENAME which is Character Data type.
Above query was failed for input_parameter 2,as we know that decode should return same data type.
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 RelatedI 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]....
Using 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.
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.
Im trying to generate this link on my result [URL].....
materialId and materialFolderId are the results of my query.. Im not sure how to combine my results and string on my query..
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 have a query that returns 11 Million rows but not all of them can be displayed in SQLDeveloper or DBVisualizer because of limited memory or other type of issues. I need to copy the entire result set to excel for further calculations.
Is there any way that i can select N number of rows out of my actual result set.
For example:
a) A result set contains 10 Million rows in total.
b) I want to display first 5 Million rows by executing a query
c) Then I want to display the remaining 5 Million rows by executing the query again with any parameter changes.
So all I want is to extract the rows of my actual result set in two or more executions, depending on the number of rows.
The below sql is giving different number of result sets while adding further columns in select clause.i.e After adding the columns 4,5,6 in the below query its giving different number of result set.In this case the result set count would be 5.
Before adding the columns 4,5,6,the result set count was 11.
SELECT PAYMENT_METHOD_MAP.NETTINGGROUP_ID,
PAYMENT_METHOD_MAP.CREDITPAYMENTMETHOD_CD,
PAYMENT_METHOD_MAP.DEBITPAYMENTMETHOD_CD,
PAYMENT_METHOD_MAP.AGENT_ID,
SETTLEMENT.NETTINGGROUP_ID,
SETTLEMENT.SETTLEMENTDATE
[code]....
I'm trying to demonstrate the working of the OCI client result cache. I've set some parameters,orcl> sho parameter result_cache
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
client_result_cache_lag big integer 3000
client_result_cache_size big integer 1000000
result_cache_max_result integer 5
result_cache_max_size big integer 1984K
result_cache_mode string FORCE
result_cache_remote_expiration integer 0
If I understand the docs correctly, that should be all that is needed.I've complied and run the cdemoqc and cdemoqc2 OCI demos, but I never get anything in the V$CLIENT_RESULT_CACHE_STATS or CLIENT_RESULT_CACHE_STATS$ views. This is probably because the sessions exit after running the queries.
So I've also tried repeating arbitrary queries through cdemo2, which gives a persistent session, but there is still nothing in those views and furthermore the v$result_cache_objects.scan_count for my queries keeps increasing. So I don't think think the client side cache is working.