SQL & PL/SQL :: Union Run In Parallel
Sep 30, 2010I have a query which has 5 unions, each clause of the union takes 1 hr to run and query results come back in 5 hrs, Is there any way I can make these clause to run in parallel?
View 13 RepliesI have a query which has 5 unions, each clause of the union takes 1 hr to run and query results come back in 5 hrs, Is there any way I can make these clause to run in parallel?
View 13 RepliesWe have very large table having data more than 1000 millions rows. We divide this table into four physical tables say A, B, C and D. The physical horizontal partition of data of this original table is done based upon their business policy.
Each partitioned table has contained data of particular business entity. Further each table has partition and sub partitions based upon business rule.
We have to retrieve data from all these tables as follows:
select a1, a2, a3, a4, a5, a6
from A
where < logical filter condition>
union all
select b1, b2, b3, b4, b5, b6
[code].....
We observed that above each query block execute in serial one after another and individual each query block capable to process data in parallel from respective table.
How does this above query able to execute each query block in parallel?
If we have not set parallel degree for a table then we can ( try to ) force parallel execution on a table using a parallel hint Does this 'parallelism' works on the index search in the query as well?
In which situations non-parallel non-partitioned table but parallel index (degree>2) will facilitate a query?
Is it better to use UNION (or) UNION ALL with DISTINCT,Which one will improve performance.
Query1:
SELECT deptno FROM emp
UNION
SELECT deptno FROM dept
Query2:
SELECT DISTINCT * FROM(SELECT deptno FROM emp
UNION ALL
SELECT deptno FROM dept)
I mean to say query1 is better (or) query2 is better,which query improves the performance.
is there any difference between
- returning from the procedure 2 ref cursors containing result set of 2 queries
- returning from the procedure 1 ref cursor containing result set of that 2 queries as one (with UNION ALL)?
Will 2nd option be faster or similar to 1st?
I am facing an issue in union clause
Below is my query Issue faced is that based on union I want to limit the result and does not want second query to give duplicate result as both queries deal with same table
SELECT TAB1.ID, TAB1.CRNCY_CODE, TAB2.SCHEME_CODE, DECODE( 'INFENG',CAST( '' AS VARCHAR(20)),
NVL(TAB2.ALT1_SCHEME_DESC,TAB2.SCHEME_DESC),TAB2.SCHEME_DESC),
TAB1.SUB_HEAD_CODE, DECODE( 'INFENG' ,CAST( '' AS VARCHAR(20)),NVL(TAB1.ALT1_SUB_HEAD_DESC ,
TAB1.SUB_HEAD_DESC),TAB1.SUB_HEAD_DESC)
[code]...
select null ID,null crncy_code,TAB2.SCHEME_CODE ,
NVL(TAB2.ALT1_SCHEME_DESC,TAB2.SCHEME_DESC),TAB2.SCHEME_DESC,null SUB_HEAD_CODE from TAB2 where TAB2.SCHEME_TYPE ='SCHEME1';
[CODE]
I'm just trying to see if there is another way of doing this query without using a UNION. The only way I can see is using a UNION but maybe I'm missing something or a way to do it without a UNION.
Result:
Select any customer within the user_states table who lives in "MO"
Select any customer within the user_cars table who lives in "MO" and has a "White" car
Select any customer within the user_plates table who lives in "MO" and has a plate of "A" or "B"
Join to the user_names table to display the customers name
So, the result would be any customer who lives in "MO" who owns a "White" car and any customer who lives in "MO" who has a plate of "A" or "B".
SQL
select b.customer_id,
b.first_name,
b.last_name
[Code]....
I have an query i.e.
I want 3 lines input in 1 line using 2 union operator like
Input:-
'i love playing
football and
volleyball'
i want the output like:-
"i love playing football and volleyball"
solve query using 2 union operator?
how can i get a union of two pl/sql tables. ??
View 2 Replies View RelatedCant find any artice on what is better to use unpivot or union all. I can achive same results using either but cant decide what would be better. For example a table has columns:
Name 1, Phone1, Name 2, Phone 2. The result I want would be:
Name 1, Phone 1
Name 2, Phone 2.
I have the following sql
select htf.escape_sc(su.sukey) a, htf.escape_sc(su.sukey) b
from udm_su su, udm_lde lde
where su.ldeid = lde.ldeid
and su.sukey in (select su_generic
[code]...
we have many tables in Cursor For Loop :
CREATE OR REPLACE PROCEDURE EBILL_BULK_UPDATE_SERVICE(in_cycle VARCHAR2)
AS
v_cnt NUMBER; -----Variable used for checking table is partitioned or not partitioned
CURSOR cur_update -----Cursor defined for Updating EBILL tables for service_id
is
SELECT table_name
, cycle_name
FROM NNP_EBILL_UPDATE
[code]....
As our requirement that Execute Immediate should work for 5 or more tables updation parallely at a time.If one table get completed then it should take next table from loop and then start the code till completion of all tables.
Is there any alternative to Union or Union all of two different table. Example would be great.
View 5 Replies View Related I've got function with combined sql statement (union all), how do I split it into two sql requests? This is to avoid time increasing of sql executing. IMHO good solution is to write two functions, how do you think?
FUNCTION f_LintOVRDUAH
(mydate date,
cid number )
[Code]....
SELECT b.KPCNO
,b.KPC_FULL_NAME
,min(c.time) in_time
FROM xxkpc_hr_personnel_v2 b
,xxkpc_fingerscan_data_v c
[code]........
I am new to SQL Oracle programming and have a question on a union query. I am trying to get results (example) for the following:
Org # Full_date Run_date
5 2/20/2012 2/20/2012
5 2/21/2012 2/21/2012
5 2/22/2012 null (there is not a record for this)
6 2/20/2012 2/20/2012
6 2/21/2012 null
6 2/22/2012 2/22/2012
7 2/20/2012 2/20/2012
7 2/21/2012 2/21/2012
7 2/22/2012 2/22/2012
The dw_time table would have the listing of all dates, (Full_date) and the dw_capacity_daily table would have the run_date. Here is my
select * from (
select distinct a.Organization_Nbr, d.full_date
from CMBHS_DW.DW_ORGANIZATION a, cmbhs_DW.DW_Organization_Identifier b, cmbhs_DW.DW_Contract c, cmbhs_dw.dw_time d
where a.ORGANIZATION_NBR = b.ORGANIZATION_NBR
[code]....
which one is better?
unloading 5 tables of same structure using a ETL tool then merging the data
using Union operator to unload 5 tables then do transformations in ETL tool
How I can get the union result of 2 queries and put them in xml result, but I want each query to be in seperate xml element. I don t want to put 1 single xmlelement and do a From then construct a virtual table uniting the 2 subqueries
I mean I don t want something like the following:
(Select
XMLAGG(
XMLELEMENT("credit",
[Code]...
Except the 2nd alternative is not working I get error message: "SQL command not properly ended"
I have one scenario in which i want to write the sql,but not able to write correct qry,
tables
1-emp
2-emp_hist
3-dept
4-dept_hist.
i want to retrieve data from the emp and hist able based on some conditions,but if data is not present in emp and dept tables.then fetch data from emp_hist and dept_hist.I have written below qry which is working fine,but my prob is i want to provide my emp_id only one place.
else i have to change my java code.
select * from emp,dept where emp.emp_id=dept.dept_id and emp_id=5
union
select * from emp_hist,dept_hist where emp_hist.emp_id=dept_hist.dept_id and emp_id=5
I would like to SELECT these 3 hardcoded titles from DUAL, and have a blank line under each, on the output in this order from the SQL. But the result does not end up that way
SQL> set heading off;
1 select '#ENCODING WINDOWS-1252' from dual
2 union
3 select ' ' from dual
4 union
5 select 'Language Section EN-US' from dual
6 union
7 select ' ' from dual
8 union
9* select 'Catalog Section Title Date Source' from dual
SQL> /
#ENCODING WINDOWS-1252
Catalog Section Title Date Source
Language Section EN-US
- - - - - - - - - - - - - - - - -
Desired Output:
#ENCODING WINDOWS-1252
Language Section EN-US
Catalog Section Title Date Source
I am writing a query and I did get it to work but it shouldn't be this hard, I feel like I am doing something wrong, and there has to be a more elegent solution.
This query works:
SELECT a.d
FROM (
SELECT S_ID a, LOOKUP_DESC d, S_CODE f
FROM SSS
JOIN LOOKUP ON S_CODE LIKE LOOKUP_CODE
UNION ALL
[Code]...
I feel like I should be able to execute the query like this: This query doesn't work:
SELECT a.d
FROM (
SELECT S_ID a, LOOKUP_DESC d, S_CODE f
FROM SSS
JOIN LOOKUP ON S_CODE LIKE LOOKUP_CODE
[Code]...
-- not some huge query
I have a requirement in SQL that I have to number each row. Hence I thought of using ROWNUM. But the sql query I'm using uses UNION operator. Hence I used like this
select a,b,rownum as 'field1' from table1
union
select c,d,1 as 'field1' from table2
Will the above query solve my purpose?
select to_char(sysdate, 'mm/dd/yyy') "DATE", to_char(sysdate, 'HH24:MI AM') "TIME", sum(bytes)/1024/1024/1024 "TOTAL_GB"
from dba_data_files
UNION ALL
select to_char(sysdate, 'mm/dd/yyy') "DATE", to_char(sysdate, 'HH24:MI AM') "TIME", sum(bytes)/1024/1024/1024 "USED_GB"
from dba_segments
[/HTML]
I like to get the output from the queries above.
DATE TIME TOTAL_GB USED_GB %USED
3/5/2013 06:00 AM 3151.24316 2330.40381 73.95
3/5/2013 12:00 PM 3151.24316 2347.41551 74.49
3/5/2013 06:00 PM 3151.24316 2349.76498 74.56
.....
[/HTML]
how I can format.
I'm combining three queries using the UNION operator.
for ex:
select 'a' from DUAL
union
select 'd' from DUAL
[Code]....
I would like to see the same order as
a
d
b
c
but it is showing as
a
b
c
d
is it possible without using ORDER BY clause?
On a tab page should be displayed the result of four indifferent queries, each based on a stored procedure.At the moment, the queries are processed serially, by the statements:
GO_BLOCK('one');
CLEAR_BLOCK(No_Validate);
EXECUTE_QUERY;
GO_BLOCK('two');
CLEAR_BLOCK(No_Validate);
EXECUTE_QUERY;
Is there a way to processes the queries parallel ?
Is it possible to run a single procedure in parallel. (Not looking for multifple, using DBMS_JOB)
I am using Oracle 9i.
I have to truncate two partitions from the same table parallelly at a time.
ALTER TABLE tablename TRUNCATE PARTITION partitioname1;
ALTER TABLE tablename TRUNCATE PARTITION partitioname2;
Huge data is present in each partition.is this possible, means it does not lock table for another alter truncate partition statement?
I am inserting 50 million records into a table MAIL_LOG. I am using the hint /*+ append parallel (MAIL_LOG, 12) */. But for my table degree is 1.
SELECT table_name, degree
FROM user_tables
WHERE table_name = 'MAIL_LOG';
I have following clarifications.
1) What degree I should use.
2) On what basis I have to give the degree.
3) Have we use constant degree all the times.
4) How to check my insert statement is using parallel degree.
5) How to find the degree at session level.
i am trying to export table using datapump in oracle 10g, this expdp takes 5 hours time, so i want use use parallel keyword in expdp,
my question is how should i know number of parallels can i use...?
I have total 8 procedure to run in parallel . and after that my 9th procedure should run.
below is my job submission procedure
create or replace procedure DURATION_ALARM_WEEKLY as
l_job number ;
begin
dbms_job.submit(l_job,'begin ALARMS_WEEKLY_CALL_OUT ; end;');
dbms_job.submit(l_job,'begin ALARMS_WEEKLY_CALL_IN ; end;');
dbms_job.submit(l_job,'begin ALARMS_WEEKLY_DURATIN_OUT ; end;');
[code].......
what is the syntax I have to do in my FINALE procedure . using DBMS_ALERT.REGISTER , DBMS_ALERT.WAITANY .....?