Solved

SQL Performance issue

Posted on 2013-05-11
7
322 Views
Last Modified: 2013-05-15
I have 2 environment say A &  B. A  is the testing phrase 1 environment and B is testing phrase 2 env.

In A env I have database which holds more data than env B. When I run a select query on Env A it get's executed fast(say 40 seconds.)Same query executing on env B takes 50 minutes.

Result of this query doesn't return any records.It will be 0.
The select query has 15 joins.No aggregation/calculation is performed in this query. It's just selecting a columns.

1.Below are my analysis details:
I saw the execution plan on both ENV.
In A estimated number & actual number of rows is 0 
In B estimated number = ~76 millions & actual number of rows is 0 

2.Fragmentation:
In env a= ~0.99 for all 15 tables
In env b = ~ 14 for all 15 tables

3.Same query executing without where clause in B is taking just 1 minute.

Should I update the statistics? 

Open in new window

0
Comment
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
7 Comments
 
LVL 23

Accepted Solution

by:
Racim BOUDJAKDJI earned 500 total points
ID: 39158379
Please post the show plan.  It looks you are missing an index.  Posting the query would help.  updating statistics and index rebuild can not hurt.  Just make sure you do it at the right time.
0
 
LVL 5

Author Comment

by:VIVEKANANDHAN_PERIASAMY
ID: 39158410
Sorry,Right now I in home and couldn't help to post the plan.

But I confirm that,both has same indexes I missed to mention this point while posting.

Just trying to understand why estimated rows is high for env B.
0
 
LVL 75

Expert Comment

by:Anthony Perkins
ID: 39158770
Just trying to understand why estimated rows is high for env B.
When was the last time statistics were updated?
0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 12

Expert Comment

by:Saurabh Bhadauria
ID: 39158947
Two things you can try to updating your statistics ..
Another optimize your query , it may help as the same can behave differently in different environment as per data volume...
And chk out your indexes...
0
 
LVL 5

Author Comment

by:VIVEKANANDHAN_PERIASAMY
ID: 39159086
My concerns here, env having large number of records executes fast ( less than minute) and environment having less records taking long time (morethan 50 minutes). Both output are the same,both have same number of indexes.

I have just like know why the estimated number of records is high(~75 million) in one and 0 in another.So like to understand what is happening inside the database engine.
0
 
LVL 75

Expert Comment

by:Anthony Perkins
ID: 39159656
I have just like know why the estimated number of records is high(~75 million) in one and 0 in another.
Let's try that again, as you may have overlooked my comment:
When was the last time statistics were updated?

Let me know if you do not understand the relevance of the question and why it may address your specific question.
0
 
LVL 5

Author Comment

by:VIVEKANANDHAN_PERIASAMY
ID: 39163715
>>Should I update the statistics? <<

Running sp_updatestats fixed the issue.
0

Featured Post

Forrester Webinar: xMatters Delivers 261% ROI

Guest speaker Dean Davison, Forrester Principal Consultant, explains how a Fortune 500 communication company using xMatters found these results: Achieved a 261% ROI, Experienced $753,280 in net present value benefits over 3 years and Reduced MTTR by 91% for tier 1 incidents.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

For both online and offline retail, the cross-channel business is the most recent pattern in the B2C trade space.
A Stored Procedure in Microsoft SQL Server is a powerful feature that it can be used to execute the Data Manipulation Language (DML) or Data Definition Language (DDL). Depending on business requirements, a single Stored Procedure can return differe…
Familiarize people with the process of utilizing SQL Server functions from within Microsoft Access. Microsoft Access is a very powerful client/server development tool. One of the SQL Server objects that you can interact with from within Microsoft Ac…
Via a live example, show how to setup several different housekeeping processes for a SQL Server.

729 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question