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Code First

EF Code First...What is Entity Framework Code First?...When you start learning Entity Framework, you will often see the term ...Entity Framework Code First.... Code first is one of the three approaches to create an entity model....Answer...In Entity Framework, code first was introduced in Entity Framework 4.1. Code First modeling workflow targets a database that doesn't exist, and Code First will create it....Code-First APIs will create the database on the fly based on your entity classes and co...

Code First vs Database First

Code First vs Database First...Code First vs Database First...When you start learning Entity Framework, you will often see the the following two terms;...Code Fist...Database First...What is the difference between ...Code First... and ...Database First... in Entity Framework?...StackOverflow Related Questions...What is the difference between 'Database First' and 'Code First to Existing Database' in Entity Framework...Code-first vs Model/Database-first [closed]...Answer...Code First Approach...Co...

Database First

EF Database First...What is Entity Framework Database First?...When you start learning Entity Framework, you will also often see the term ...Entity Framework Database First.... Database first is one of the three approaches to create an entity model....Answer...In the Entity Framework, the Database First Approach provides an alternative to the Code First by creating POCO classes from the existing database....Database first approach is used when a database is ready; then Entity Framework will comp...

DbSet

DbSet...In Entity Framework, the DbSet class represents an entity set that can be used for the database operation, such as create, read, update, and delete....The context class must include the DbSet type properties for the entities which map to database tables and views....The DbSet is an implementation of the Repository pattern....public class BookStore : DbContext { public BookStore() : base(FiddleHelper.GetConnectionStringSqlServer()) { } public DbSet<Author> Authors { get; ...

EF Power Tools

Power Tools...Entity Framework 6 Power Tools... are very useful design-time utilities which can be used in Visual Studio....You can download and install it from ...Visual Studio Marketplace.......When right-clicking on a file containing a derived DbContext class, the following context menu functions are available:...View Entity Data Model (Read-only):... It displays a read-only view of the Code-First model in the Entity Model Designer....View Entity Data Model XML:... It displays the EDMX XML re...

Many to Many

Many-to-Many Relationships...In a many-to-many relationship, each row of data in one table is linked to many rows in the second table and vice versa....A many-to-many relationship occurs when multiple records in one table are associated with multiple records in another table....For example, a many-to-many relationship exists between ...Book... and ...Category... entities....Let's say we have ...Author... and ...Book... entities....public class Book { public int BookId { get; set; } publi...

Model First

EF Model First...What is Entity Framework Model First?...Model First allows you to create a new model using the Entity Framework Designer and then generate a database schema from the model....The model is stored in an EDMX file (.edmx extension) and can be viewed and edited in the Entity Framework Designer....The classes that you interact with in your application are automatically generated from the EDMX file....Create Model...Let's create a new empty project and add the EntityFramework NuGet pa...

One to Many

One-to-Many Relationships...In a one-to-many relationship, each row of data in one table is linked to one or more rows in the second table. It is the most common type of relationship....A one-to-many relationship happens when the primary key of one table becomes foreign keys in another table....The foreign key is defined in the table that represents the many end of the relationship....Let's say we have ...Author... and ...Book... entities....public class Author { public int AuthorId { get; s...

One to One

One-to-One Relationships...In a one-to-one relationship, each row of data in one table is linked to zero or one row in the second table. For example, the ...Author... and ...AuthorBiography... have a one-to-one relationship....This type of relationship is not common because most information related in this way would be an all-in-one table....When you define a one-to-one relationship in your model, you use a reference navigation property in each class....Let's say we have an ...Author... class wh...

Relationships

Relationships...In the context of relational databases, a relationship exists between two relational database tables when one table has a foreign key that references the primary key of the other table. In Entity Framework, a relationship defines how two entities relate to each other....Entity framework supports three types of relationships....One-to-One...One-to-Many...Many-to-Many...One-to-One Relationship...In a one-to-one relationship, each row of data in one table is linked to zero or one ro...

Table per Concrete

Table Per Concrete...What is Inheritance Type in Entity Framework?...Entity Framework code first creates tables for each concrete domain class. You can also design your domain classes using inheritance....In Object-oriented programming, we can include ..."has a"... and ..."is a"... relationship, whereas in a SQL-based relational model we have only a ..."has a"... relationship between tables and there is no support for type inheritance....So, how would you map object-oriented domain classes with ...

Table per Hierarchy

Table Per Hierarchy...What is Inheritance Type in Entity Framework?...Entity Framework code first creates tables for each concrete domain class. You can also design your domain classes using inheritance....In Object-oriented programming, we can include ..."has a"... and ..."is a"... relationship, whereas in a SQL-based relational model we have only a ..."has a"... relationship between tables and there is no support for type inheritance....So, how would you map object-oriented domain classes with...

Table per Type

Table Per Type...What is Inheritance Type in Entity Framework?...Entity Framework code first creates tables for each concrete domain class. You can also design your domain classes using inheritance....In Object-oriented programming, we can include ..."has a"... and ..."is a"... relationship, whereas in a SQL-based relational model we have only a ..."has a"... relationship between tables and there is no support for type inheritance....So, how would you map object-oriented domain classes with the ...