Same query runs with a lot of difference of speed on two machines

Dear All,
I am facing a strange problem.
A query which when run in SQL*Plus/Toad/Oracle SQL Developer, gives output within fraction of seconds. But when i run the same query in my home it takes about hour to produce output.
Using schema script i managed to have the same database setup at my home. My home PC is having better processor than company PC and having same memory.
In company the database server is linux and i access it using a Oracle client, but in home it is on same PC.
I am sure that i am running the same query with the same database as i had run another queries successfully on the same database.
Then how do this come?
Am i missing something? Any idea?
Do revert.
Thanks in advance.
-Sameer

Its possible that network communcations is part of what you're seeing. TOAD can wait until it gets back all the data you are querying; a lot of data could take awhile to transfer off-site. If not network it could be something else in your environment.
Try writing a PL/SQL cursor to be executed inside the database without bringing data back to the client and time it to see if merely selecting the data on the server takes a long time.

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Query on a table runs more than 45mins(after stats) and same query runs 19secs(before stats - rebuild)

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{code}
SQL> explain plan
2 set statement_id = 'SLOW'
3 for
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{code}
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I have a query which is taking a long time to return the results using the Oracle client.
When I run this query on our database server (Unix/Solaris) it completes in 80 seconds.
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You may get the same results depending on the client you are using. Post your question in a forum for whatever client you are using.

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In forms and cursors you can not use scalar subqueries as you do. You have to use joins!
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from
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A massive difference in logical reads usually hints at differences in the query plan.
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Hi!
We just had some performance problems in our production system and I would like to ask for some advice from you.
We had a select-query that was run from USER1 on SCHEMA1, and it ran a table scan on a huge table.
Using session browser in TOAD I copied the Sql-statement, logged on SCHEMA1 and ran the same query. I got a different execution plan where I avoided the table scan.
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How is it possible that the same query get different execution plans when running in two different schemas at the same time.
Some more information:
The user USER1 runs "alter session set current_schema=SCHEMA1;" when it logs on. Besides that it doesn't do anything so session parameter values are the same for USER1 and SCHEMA1.
SCHEMA1 is the schema owning the tables.
ALL_ROWS is used for both USER1 and SCHEMA1
Our database:
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
PL/SQL Release 9.2.0.8.0 - Production
CORE 9.2.0.8.0 Production
TNS for Linux: Version 9.2.0.8.0 - Production
NLSRTL Version 9.2.0.8.0 - Production
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Thanks for clarification of the schema structure.
What happens if instead of setting the current session schema to SCHEMA1, if you simply add the schema name to alle tables, views and other objects inside your select statement?
As in select * from schema1.dual;I know that this is not what you want eventually, but it might help to find any misleading objects.
Furthermore it is not clear what you meant with: "avoided a table scan".
Did you avoid a full table scan (FTS) or was the table completely removed from the execution plan?
Can you post both plans?
Edited by: Sven W. on Mar 30, 2010 5:27 PM

Abnormal, Same query get data in sql but not working on Fron-end

Dear,
Version :Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
We have created packed in oracle database befor two months ago & was working fine, but since morning select statment in package is not working while running via application which mentioned below and raise not data found but surprising thing is that same query is getting data when we execut on sql plus return one record.
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Hmmm. I don't have the time to verify this right now. Anyway, reindexing is good enough to flush the cache of most plans.
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Have you researched what values the initial plan is sniffed for?
As Erland said adding space in query ,I don?t know adding space means just add additional space in the query so it hashes a different values .Please advice .
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Erland Sommarskog, SQL Server MVP, [email protected]

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