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This article mainly explains "what is the method of constructing database by LINQ to SQL". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Next, let the editor take you to learn "what is the method of constructing a database by LINQ to SQL"?

LINQ to SQL concept

What is LINQ to SQL? LINQ to SQL is an implementation of O/RM (object-relational mapping) in the .NET Framework "Orcas" release, which allows you to use .NET classes to generate a relational database. You can then use LINQ to query the database from the object, update / insert / delete. LINQ to SQL fully supports transactions, views, and stored procedures. It also provides a convenient way to validate aggregate data and business logic rules in your data model.

LINQ to SQL Construction Database

A designer is built into VS "Orcas" that provides a simple way to visually transform a database into an LINQ to SQL relational model. My next blog will go a little further to introduce how to use the designer (you can see this video I recorded in January on how to use it)

Through the LINQ to SQL designer, I can easily design the following "Northwind" database model as an example:

The figure above defines four entity classes: Product, Category, Order and OrderDetail. The properties of each class are mapped to the corresponding table in the database. An instance of each class represents a row of records in the data table.

In the figure above, the arrows in the four entity classes represent the relationships between the entities. They are mainly generated from the primary key / foreign key relationship in the database. The direction of the arrow on the designer indicates whether the relationship is one-to-one or one-to-many. Based on this, strongly typed attributes will be added to this entity class. For example, there is an one-to-many relationship between the Category class and the Product class above. This means that I can have a "Categories" property that represents all the collection of product objects in this class. The Product class will have a "Category" attribute to point to an instance of the Category class, which indicates the category to which the product belongs.

On the right side of the LINQ to SQL designer are stored procedures that interact with our database model. In the example above, I added a "GetProductsByCategory" stored procedure. It takes a categoryID as an input parameter and returns a product sequence. The following example code shows how to call the stored procedure.

At this point, I believe you have a deeper understanding of "what is the method of LINQ to SQL to construct a database". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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