Solving common problems with Compiled Queries in Linq to Sql for high demand ASP.NET websites - Omar AL Zabir blog on ASP.NET Ajax and .NET 3.5. If you are using Linq to SQL, instead of writing regular Linq Queries, you should be using Compiled Queries. if you are building an ASP.NET web application that’s going to get thousands of hits per hour, the execution overhead of Linq queries is going to consume too much CPU and make your site slow. There’s a runtime cost associated with each and every Linq Query you write. The queries are parsed and converted to a nice SQL Statement on *every* hit. It’s not done at compile time because there’s no way to figure out what you might be sending as the parameters in the queries during runtime.
So, if you have common Linq to Sql statements like the following one throughout your growing web application, you are soon going to have scalability nightmares: var query = from widget in dc.Widgets where widget.ID == id && widget.PageID == pageId select widget; var widget = query.SingleOrDefault(); There’s a nice blog post by JD Conley that shows how evil Linq to Sql queries are: So, be it.
LINQ to Objects. Exclusive offer: get 50% off this eBook here LINQ Quickly — Save 50% A Practical Guide to Programming Language Integrated Query with C# by N Satheesh Kumar | December 2007 | .NET Microsoft LINQ to Objects means that we can use LINQ to query objects in a collection. We can access the in-memory data structures using LINQ. In this article, author N. Without LINQ, we would have to go through the values one-by-one and then find the required details.
The following example shows an integer array that contains a set of integers. The integers variable contains an array of integers with different values. The actual query execution happens when the query variable is iterated through the foreach loop by calling GetEnumerator() to enumerate the result. The twoDigits variable will hold the query to fetch the values that are greater than or equal to 10. If we want only the first four values from a collection, we can apply the Take() query operator on the collection object. About the Author : N. Building LINQ Queries at Runtime in C# 7 tricks to simplify your programs with LINQ. Ever since I learned about LINQ, I keep discovering new ways to use it to improve my code. Every trick makes my code a little bit faster to write, and a little bit easier to read. This posting summarizes some of the tricks that I came across. I will show you how to use LINQ to: If you have your own bag of LINQ tricks, please share them in the comments!
Also, if you like this article, you may like my next article, Extended LINQ: additional operators for LINQ to objects. 1. Often, you need to initialize elements of an array to either the same value, or to an increasing sequence values, or possibly to a sequence increasing or decreasing by a step different from one. In the following code sample, the first line initializes a to an array of length 10 with all elements set to -1, the second line initializes b to (0,1,..9), and the third line initializes c to (100,110,…,190): 2. A friend asked me a C# question: is there a way to iterate over multiple collections with the same loop? 3. 4. 5. 6. Split List into Sublists with LINQ. Compiled or Bust? While I may have mixed emotions toward LINQ to SQL, we've had great success with it on Stack Overflow. That's why I was surprised to read the following: If you are building an ASP.NET web application that's going to get thousands of hits per hour, the execution overhead of Linq queries is going to consume too much CPU and make your site slow.
There’s a runtime cost associated with each and every Linq Query you write. The queries are parsed and converted to a nice SQL Statement on every hit. It’s not done at compile time because there’s no way to figure out what you might be sending as the parameters in the queries during runtime. So, if you have common Linq to Sql statements like the following one .. var query = from widget in dc.Widgets where widget.ID == id && widget.PageID == pageId select widget; var widget = query.SingleOrDefault(); .. throughout your growing web application, you are soon going to have scalability nightmares. J.D. Quite the mystery. db.ExecuteQuery. Recursively Traversing a Hierarchical Data Structure Using LINQ. Download source - 22.29 KB Introduction This article makes an attempt to show how to query for objects in a tree like hierarchical data structure using LINQ and without additional overhead of flattening the data structure or looping through the elements.
Background Unfortunately at the time of writing this article, there has not been a recursive query operator defined for LINQ. Therefore there is no direct method to query for objects in a hierarchical data structure as you would do for a flat object collection. For querying a flat object collection, you would probably write something like: myItems.FindAll(i => i.Id == 25) For a hierarchical collection, wouldn't it be cool if we were able to write something similar to query for objects anywhere in the hierarchy: myItems.Traverse(i => i.Id == 25) This can be achieved by writing an extension method which internally uses the Y Combinator to recursively traverse the hierarchy.
Y Combinator Extension Method Usage Limitations. Quick Examples on LINQ To SQL Performance Tuning - Performance Profiling Your O/R Mapper. 10 Tips to Improve your LINQ to SQL Application Performance | Sidar Ok Technical Blog ! Hey there, back again. In my first post about LINQ I tried to provide a brief(okay, bit detailed) introduction for those who want to get involved with LINQ to SQL. In that post I promised to write about a basic integration of WCF and LINQ to SQL working together, but this is not that post. Since LINQ to SQL is a code generator and an ORM and it offers a lot of things, it is normal to be suspicious about performance of it.
These are right up to a certain point as LINQ comes with its own penalties. But there are several benchmarks showing that DLINQ brings us up to %93 of the ADO.NET SQL DataReader performance if optimizations are done correctly. Hence I summed up 10 important points for me that needs to be considered during tuning your LINQ to SQL’s data retrieval and data modifying process: 1 – Turn off ObjectTrackingEnabled Property of Data Context If Not Necessary If you are trying only to retrieve data as read only, and not modifying anything, you don’t need object tracking.