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.
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 am working on this assignment question for class:
Write a SELECT statement that returns a single value that represents the sum of the largest unpaid invoices for each vendor (just one for each vendor). Use an inline view that returns MAX(invoice_total) grouped by vendor_id, filtering for invoices with a balance due
What I have coded so far is below
SELECT i.vendor_id,
To_char(SUM(invoice_total), '$9,999,999.99') AS sum_invoice_total
FROM invoices i
join (SELECT vendor_id,
[code]...
I am getting some results which I have attached. I'm not sure if I'm capturing the "largest unpaid invoices for each vendor" part of the question. Yielding to the knowledge the group and trying to use the proper posting etiquette. I have attached my output screen as well.
the execution steps of inline view?importance&advantage of inline view?.Also reference link where i can get more information about inline view(i.e. basics to advanced),exercises and interview questions.
View 3 Replies View Relatedbelow query, first query is giving proper output i.e. 0 while second is giving wrong output i.e. 1.
Why this happen , what's wrong in using count in inline view ?
selecT count(*)
from (select *
from dual
where 1 = 2
union
select * from dual where 1 = 2);
[Code]....
there is a diff. problem for me.when i create table through inline view then it shows 2246 records but if i check these records only in select statement then it shows 124 records. i cant understand how table shows 2246 records even then atual records in inline view shows only 124 records.
following is a query
create table sam as
select * from
((
select distinct stck.item_code
from (
select item_code,bal
[code]...
which one is better in performance point of view and why between inline view and correlated query.
View 5 Replies View RelatedCan I update inline view like below?
update
(select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 55) a,
(select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 3) b
where a.survey_id = b.survey_id and substr(a.question_uid , 3) = substr(b.question_uid, 2))
set b.answer = a.answer;
My second question is: The following query is giving error. What can I do?
update answers ans set (ans.answer) = (with a as (select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 55),
b as (select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 3)
select a.answer from a join b on a.survey_id = b.survey_id and substr(a.question_uid , 3) = substr(b.question_uid, 2) and b.answer_id = ans.answer_id) where ans.main_group_id = 3;
SQL Error: ORA-00904: "ANS"."ANSWER_ID":
Attached query is running fine if inline view B (Marked in Comments) returning value. If inline view B returns NULL then it fails to return result. I want if Inline view B is returning NULL then it should pass ZERO to main query.
View 2 Replies View RelatedIs there a function that allows the following?
select SOME_FUNCTION('N','E','S','W') from dual;
That returns
N
E
S
W
Currently I'm just doing the following
WITH direction AS
(SELECT 'N' dir FROM DUAL
UNION
SELECT 'E' FROM DUAL
UNION
SELECT 'S' FROM DUAL
UNION
SELECT 'W' FROM DUAL)
SELECT *
FROM direction;
Below is the query where I need to filter the data using window function.
I don't want to use inline view for mt query because i need to use the same query in OWB which it wont support.
Select a.Physical_Id,
a.Booking_Begin_Date,
a.Booking_End_Date,
[Code]....
I Cannot use below query in OWB Which is Inline View
----------------------------------------------------------------------------
Select b.* From
(Select a.Physical_Id,
a.Booking_Begin_Date,
[Code].....
After searching a lot on net the differences between inline view and subquery that i came across are
1) you can use order by in inline view but not in subquery.
2) you can use alias for inline view but not subquery.
i have to fetch the same outcome using both the functionality respectively, then what is the technical impact/better.
Just want to confirm, that where Oracle stores data fetched from inline view.
I am asking, as I am making an inline view on a very large table and its getting failed with TEMP space error.
how joins work with in-line views.I have a query and its explain plan as below:
SELECT e.ename,e.deptno,d.dname FROM
dept d,
emp e
WHERE e.deptno=d.deptno
AND e.deptno=20
[code]....
I do not find any difference in both the explain plans. Both are same. In my second query, the filtered rows will be joined to dept table. And hence the baggage will reduce.But how can I verify that in-line view has worked better?
I have a view, below, which does few left outer joins to the same V_MARKET view to get data i need. When I run SQL by itself, ut runs pretty fast, 2-5 seconds. But when I do "select * from V_DEPT_DATA where busines_date = '01-APR-10'", it takes more than 10 minutes to run. I added all needed indexes and still have problems with it .
CREATE OR REPLACE VIEW V_DEPT_DATA
AS
SELECT
v1.business_date ,
v1.division ,
v1.department ,
v1.account ,
en.trader ,
[code]........
I've 2 tables in schema A.
1) TXN_HD_FCT (This table has 6 billion records. Has fields TXN_DT, CUST_ID, TXN_AMT, TXN_ID and the table is partitioned on TXN_DT. We load data approximately 600K+ records to this table every day
2) RELINK_CUST (This table has 2 fieds CUST_ID and NEW_CUST_ID). We load data approximatley 100-200K+ records every day into this table. This table has total 10MM+ records now.
Now i need to create a table (TXN_UPD_HDR_FCT) in Schema B by joining above 2 tables using below query every day
CREATE TABLE TXN_UPD_HDR_FCT
select a.TXN_DT,
nvl(b.new_cust_id, a.cust_id) as cust_id,
a.txn_amt,
a.txn_id,
from schema_A.TXN_HD_FCT a,
schema_A.RELINK_CUST b
where a.cust_id = b.cust_id(+);
We update CUST_ID to NEW_CUST_ID based on some rules (and keep it in the table RELINK_CUST) and need to take this new_cust_id while building the table TXN_UPD_HDR_FCT.
Building this table is taking approximately 4+ hours every day. just refresh only records from TXN_HDR_FCT whose CUST_ID is changed or any records inserted into TXN_HDR_FCT? I read about Materialized views but not sure how can i create MV logs on 2 tables? If i use materialized views do i need to create indexes every day?
I 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
I have an issue in materialized view which has got one of the null able column and query on this column taking approximately 2 mins where as other indexed columns takes less than 10 sec.
Here is the summary
SQL> Select Count (1), Count (VAT_NO) From Mv_customer;
COUNT(1) COUNT(VAT_NO)
---------------------------------
2893561 1516
If an index is created on VAT_NO will that improve the performance. What kind of index can be created considering very less number of records has got VAT_NO
I have a view on base tables holding historical data for previous 60 months(one table per month) with union all operators.create index on those base tables will improve performance or creating a primary key with disabled novalidate will improve for retrieving data?
The view has around 8 million data and used as a fact table with 4 dimension tables.A DTS package from MSSql side refreshes OLAP cube by retrieving data from these tables in oracle.
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
If you have 3 tables (yr09, yr10,yr11) one with 2009 data, 2010 and 2011 data respectively. And a view (vw_yr091011) with a "union all" on all three.
Question: Will the performance be same for the following two queries ?
Question: Will Oracle read all 3 tables in the view when we search for only one year ?
select count(*) from yr09
where year = 2009;
-- vs
select count(*) from vw_yr091011
where year = 2009;
The following link says yes, the performance remains the same.
Link: [URL]..........
when I tried on a volume of 14000 records. The count came out same but the view took 50 more sec. And the explain plan shows it accessed all three tables.
I need to create a Materialized View, which should refresh every Tuesday and Friday at 5am.
CREATE MATERIALIZED VIEW DUAL_MV
TABLESPACE USERS_SMALL
REFRESH NEXT NEXT_DAY(TRUNC(SYSDATE), 'TUESDAY') + 05/24
AS SELECT * FROM DUAL;
I can do it for single day like above, but how to refresh on multiple days, using create materialized view syntax .
I have a base table with ~20 mio. records with two FAST REFRESH Materialized Views based on that table using various aggregate functions in their view definition.
The problem is, when e.g. one record changes in the base table, I see two records in the MV log table MLOG$, but invoking the fast refresh mechanism by using using:
dbms_snapshot.refresh('mv1', 'f');
dbms_snapshot.refresh('mv2', 'f');
Is still running after ~20 minutes now.
base on performance it is better to retrieve data from view or mention the table names directly?
I have a select statement in from clause one of my table is view (which is having data collected from four tables) my question is whether performance of querry will be improved if i use directly all tables( four tables of a view) instead of a view
we're having a few tables which queries about 10.000 articles. As we don't show them all at once we are using pagination and use the rownum to show only a limited number of the results.
Now as these queries are pretty complex we have to optimize them and since we use pagination we have to call our query twice (first we make a count(*) and then we call the small resultset of a few rows). Ofcourse we are looking for a solution to call it only once and still use the pagination. We could load the whole resultset of 10.000 results and let java show only a few but that makes our line between the oracle and webserver pretty heavy. Is there a way to call the total number of results and give back only a small resultset just in one query?
When to use inline query and to use join.
View 3 Replies View RelatedI have been using With for many queries for readability. This most recent query seemed to be taking a bit longer to run and I didn't think much of it until a colleague showed me their version (totally different sql statement) which ran faster, but seemed more complicated and had more lines of code. I noticed that the other version did not use with. I moved the sql of the with into the join and the query ran faster dropping from 30 seconds to 798 msecs. The question is am I sacrificing speed for readability by using With, or it really depends on the overall sql statement.
Here is the query using WITH:
with prev as
(
select person_uid, id, name, academic_period,
case when enrolled_ind = 'Y' and registered_ind = 'N' and student_status = 'AS' then 0 else 1 end as enreg_stat,
[Code]....
I have created a few flash charts using APEX4.2. Is there a way for the user to view the chart and then email it as an inline image to someone? I know that the user can save the chart as PDF file, then send it as an attachment via Outlook ( or similar system), but can I integrate these manual steps to one ( template), similar to the IR report's download feature ?
View 0 Replies View Relatedcan we change the existing materialized view to normal view? if yes how?
View 2 Replies View RelatedI'm trying to create a Materialized View on a remote database from a simple view. The reason is, the data owners don't want to grant explicit tables privileges to external subscribers.
A new schema is created to publish data in the form of a view. I've created mlogs on the master tables, and granted them to the subscriber, but it's still complaining about a missing primary key on the view. A primary key does exist in the master table.
Is there another work around for this situation without having to work inside the data sources' environment?