Solved

Linq Performance about large table

Posted on 2008-10-24
2
691 Views
Last Modified: 2013-11-11
Hi,

Suppose i have a table MYTABLE with millions of records.
Suppose i use this code :

var result = from e in DC.MYTABLE
                    where ....
                     select e;
foreach( MYTABLE record in result )
{
}

In SQL server management studio, if i run the equivalent query, i will get a long long very long result set.
In LINQ, what am i supposed to understand when the foreach is executed ?

1/ All millions of records from MYTABLE are sent ONCE to my application and stored in memory ?

2/ OR at each FOREACH statement, only one record is sent at a time by SQL server to my application ?

What is the correct answer ?
(Because i cannot use the Take() linq statement, i must browse the recordset)

Thank you
0
Comment
Question by:mars
2 Comments
 
LVL 62

Accepted Solution

by:
Fernando Soto earned 125 total points
ID: 22800244
Hi mars;

When the Linq query is executed in the foreach loop it first executes the query and gets all the records. The only way to brows the records is to use the Take and Skip methods.

The following link has tips that can help to make Performance better. Tip 9 talks about the Take and Skip methods.

10 Tips to Improve your LINQ to SQL Application Performance
http://www.sidarok.com/web/blog/content/2008/05/02/10-tips-to-improve-your-linq-to-sql-application-performance.html

Fernando
0
 

Author Comment

by:mars
ID: 22800373
I was afraid of your answer, and it's very a pity that LINQ works like this.
Thank you
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

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

Suggested Solutions

Summary Displaying images in RichTextBox is a common requirement with limited solutions available. Pasting through clipboard or embedding into RTF content only support static images.  This article describes how to insert Windows control objects int…
Welcome my friends to the second instalment and follow-up to our Minify and Concatenate Your Scripts and Stylesheets (http://www.experts-exchange.com/Programming/Languages/.NET/ASP.NET/A_4334-Minify-and-Concatenate-Your-Scripts-and-Stylesheets.html)…
Windows 10 is mostly good. However the one thing that annoys me is how many clicks you have to do to dial a VPN connection. You have to go to settings from the start menu, (2 clicks), Network and Internet (1 click), Click VPN (another click) then fi…
Many functions in Excel can make decisions. The most simple of these is the IF function: it returns a value depending on whether a condition you describe is true or false. Once you get the hang of using the IF function, you will find it easier to us…

911 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

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now