Getting Started With Lin. Q To SQL Tutorial With C Code Examples. Here, I will discuss about basic Lin. Q to SQL tutorial overview, then how to get started very quickly with its usage on our C. NET based applicationsThis can be used in both desktop and web applications in the exactly same way. Besides, I will also discuss about using select query in linq to retrieve data and traverse through the query resultsin case of multiple result objects. To understand this tutorial properly, You should have handy knowledge on c and have visual studio 2. NET Framework 3. 0 to successfully able to run LINQ To SQL examples. What Is LINQ To SQLFull meaning of LINQ is Language Integrated Query, which replaces the traditional sql query execution process. Moreover, it doesnt only applicable to manipulate database results, but it can also be used to manipulates arraylist collections. Lin. Q was released as part of the. NET framework 3. 0 and can be used from languages supported by. NET framework like C, VB etc. The term LINQ To SQL refers to the technology by which we can use LINQ for access SQL Databases. Here in this tutorial, I will show step by step ways to get started with LINQ To SQL programming with C. Read All Lin. Q Tutorials By Code. Samplez. com. Mapping LINQ To SQL Class From SQL Server Database First step to be able to use Lin. Q on our SQL database, we will need to define a way, by which. NET can recognize the database as ClassesObjects, so we will need to map the database tablesstored procedures to Lin. Q to SQL classes. Multiple Dbml Files In One Project 2017' title='Multiple Dbml Files In One Project 2017' />C C Programmiersprache IT C Country X. Adressierung, Land IT C Kohlenstoff Chemisches Element C Kollektor Transistor Elektronik C privater Konsum. LINQ to SQL only supports 1 to 1 mapping of database tables, views, sprocs and functions available in Microsoft SQL Server. Its a great API to use for quick data. To begin working with LINQ to SQL in Visual Studio 2008 you will need a database that you can query and a copy of MS SQL Server or SQL Express. In this. To accomplish this task successfully, first open your project in the solution explorer, right click add new item, in the data categories, there is a type named LINQ To SQL Classes. Select that. We will get a. The designer interface has two part, one for dragging tables from server explorerto create classes from tables automatically, another is for methods where we can drag stored procedures etc. After dragging all classes from server explorer, we are done. Here is a sample db structure that we will be using on the way of this tutorial Select Data Using Lin. Q To SQL After we make the DBML files appropriately, its very simple to get started our actually implementation in c code. Most interesting thing is, we will be using sql query like syntax right from the c code for getting database results. Suppose, we are trying to validate a user against a given usernamepassword from database. Multiple Dbml Files In One Project З•™е­¦' title='Multiple Dbml Files In One Project З•™е­¦' />Here is a sample codes of a function for such purpose. Is. Valid. Userstring user. Name, string pass. Word. DBName. Data. Context my. DB new DBName. Data. Context. var user. Results from u in my. Im not quite sure stackoverflow is a place for such a general question, but lets give it a try. Being exposed to the need of storing application data somewhere, I. Multiple Dbml Files In One Project Of ScienceDB. Users. where u. Username user. Name. u. Password pass. Word. select u. return Enumerable. Countuser. Results 0. You can see, the syntax is much like sql, but not exactly same though. First, when you create a new dbml file with name DBName. Data. Context class in. DBName. Data. Context These Data. Context classes are now responsible for. NET To Database communications. In the linq query syntax, this object will be used to present the database. Next, whenever we write something like from u in my. This article has multiple issues. Please help improve it or discuss these issues on the talk page. Learn how and when to remove these template messages. ASP. NET is an opensource serverside web application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow. In this article I am explaining partial classes in C language with an example. A partial class splits the definition of a class over two or more source files. DB. Users visual studio automatically treat u as an object of User class, that actually represents databases users tableyou will might also notice if your database table contains plural form like users, it automatically makes it as singular when creating the linq to sql class like User, though table name used in the query will still be plural. Next, notice one of the most useful advantage of LINQ, if you make any kind of data type mistake in your code, you will be notified immediately while compiling your project. This will saves lots of your debugging time and lessen the db errors at the same time. Multiple Dbml Files In One Project Israel' title='Multiple Dbml Files In One Project Israel' />NET class, so its simply validating the propertys data type. Of course, you will have to remember that, if you change your db structurecolumn data type etc later on, you should have to drag the tables from server explorer to dbml once again to reflect your db changes to the linq to sql classes. Next, Note the result is assigned to a variable of type var. This data type is also new from. NET framework 3. 0 and used to represent data with dynamic types. That means, here any kind of data returned from the linq query will be assigned to that variable and you will have to just cast that to the proper data type. Next, Enumerable. Count, this function count the number of rowsOr number of objects returned by the query. You can use this function on var type result object without need of casting it to any intermediate form. Select Operation Without SQL Syntax in Lin. Q The above example showed how to use Lin. Q To SQL syntax for querying database for retrieve data. However, there is alternative simple ways also for avoid using query like syntax by using integrated Where method. Here is a simple code example to accomplish that. Is. Valid. Userstring user. Name, string pass. Word. DBName. Data. Context my. DB new DBName. Data. Context. Listlt User users my. DB. Users. Whereu u. Username user. Name u. Passwordpass. Word. Count 0. return true. Retrieve A Single Row With Lin. Q On the above example, we have learned to execute a SQL like statement. However, LINQ provides much more flexibility than that. Like, if you need a single itemrow from database table, it can be done very easily. Here is a code sample for such cases. User Get. Userstring user. Name. DBName. Data. Context my. DB new DBName. Data. Context. User user my. DB. Users. Singleu, u. User. Name user. Name. The above example will return a single record from database table. In the u. User. Name user. Name part, you can mention any column name you want to be validated. Foreach Loop Through All Lin. Q To SQL Returned Results In case, when Lin. Q query returns multiple results, we often need to traverse through all the result rowshere all Lin. Q objects and process in some way. Artcut 2006 Software here. It can be done very easily with a foreach loop. Although for loop also can be used, however foreach is better in performanceto know details, you can refer to my for vs foreach article. User user in user. Results. checking the result as like object. Role admin. References I have tried to give you a very basic overview for getting started with LINQ To SQL. However, in real application, you will be needed to know much more details. Here are some resource links, where you will get some more useful resources to enrich your knowledge base with in LINQ I will try to post more articles about some more advanced Lin. Q to SQL tutorials. Wish you a very good journey with LINQ programming.