Language Integrated Query

Microsoft Language Integrated Query (LINQ) offers developers a new way to query data using strongly-typed queries and strongly-typed results.By using strongly-typed queries and results, LINQ improves developer productivity with the benefits of IntelliSense and compile-time error checking.

Microsoft provides to approaches for this:-
1:- LINQ to SQL.
2:- LINQ to ENTITIES.

What Is LINQ to SQL?

LINQ to SQL is an object-relational mapping (ORM) framework that allows the direct 1-1 mapping of a Microsoft SQL Server database to .NET classes.LINQ to SQL provides a runtime infrastructure for managing relational data as objects without losing the ability to query.

We can test our linq queries using Linq Pad.
Which we can download from following link:-

http://www.linqpad.net/

There are various version of Linq pad are available. We can choose the version according to the .Net Framework Version.

Here Some Linq Examples are:-(These all are written in C# statement(s).)
1:-
int[] numbers = { 15, 24, 31, 23, 49, 18, 26, 17, 22, 30 };

var lowNums =
from n in numbers
where n < 25
select n;

Console.WriteLine("Numbers < 25:");
foreach (var x in lowNums)
{
Console.WriteLine(x);
}

Result:-
Numbers < 25:
15
24
23
18
17
22

2:- Order by Demo
string[] words = { "Ashish", "Shashank", "Shikhar","Nihil","Arpit" };

var sortedWords =
from w in words
orderby w.Length,w
select w;

Console.WriteLine("The sorted list of words:");
foreach (var w in sortedWords)
{
Console.WriteLine(w);
}

Result:-
Arpit
Nihil
Ashish
Shikhar
Shashank

Well Friends I'll try to write some more good example in future.
Byeee..