- Entity F - Nested Entity Types
- Entity F - Multiple DbContext
- Entity F - Code First Migration
- Entity Framework - Seed Database
- Entity Framework - Fluent API
- Entity Framework - Data Annotations
- Entity Framework - First Example
- Entity F - Code First Approach
- Entity Framework - Colored Entities
- Entity Framework - Track Changes
- Entity Framework - Validation
- Entity Framework - Explicit Loading
- Entity Framework - Lazy Loading
- Entity Framework - Eager Loading
- Entity Framework - Migration
- Entity Framework - Inheritance
- Entity Framework - Spatial Data Type
- Entity F - Command Interception
- Entity F - Command Logging
- Entity F - Projection Queries
- Entity Framework - Persistence
- Entity F - Asynchronous Query
- Entity Framework - Enum Support
- Entity Framework - Native SQL
- Entity F - Table-Valued Function
- Entity F - Disconnected Entities
- Entity F - Stored Procedures
- Entity Framework - Index
- Entity Framework - Views
- Entity Framework - Transaction
- Entity Framework - Concurrency
- Entity F - Database Operations
- Entity Framework - DEV Approaches
- Entity F - Database First Approach
- Entity F - Model First Approach
- Entity F - Code First Approach
- Entity Framework - Lifecycle
- Entity Framework - Relationships
- Entity Framework - Types
- Entity Framework - DbContext
- Entity Framework - Data Model
- Entity Framework - Database Setup
- Entity F - Environment Setup
- Entity Framework - Architecture
- Entity Framework - Overview
- Entity Framework - Home
Entity Framework Resources
Selected Reading
- Who is Who
- Computer Glossary
- HR Interview Questions
- Effective Resume Writing
- Questions and Answers
- UPSC IAS Exams Notes
Entity Framework - Database First Approach
In this chapter, let us learn about creating an entity data model with Database First approach.
The Database First Approach provides an alternative to the Code First and Model First approaches to the Entity Data Model. It creates model codes (classes, properties, DbContext etc.) from the database in the project and those classes become the pnk between the database and controller.
The Database First Approach creates the entity framework from an existing database. We use all other functionapties, such as the model/database sync and the code generation, in the same way we used them in the Model First approach.
Let’s take a simple example. We already have a database which contains 3 tables as shown in the following image.
Step 1 − Let’s create a new console project with DatabaseFirstDemo name.
Step 2 − To create the model, first right-cpck on your console project in solution explorer and select Add → New Items…
Step 3 − Select ADO.NET Entity Data Model from middle pane and enter name DatabaseFirstModel in the Name field.
Step 4 − Cpck Add button which will launch the Entity Data Model Wizard dialog.
Step 5 − Select EF Designer from database and cpck Next button.
Step 6 − Select the existing database and cpck Next.
Step 7 − Choose Entity Framework 6.x and cpck Next.
Step 8 − Select all the tables Views and stored procedure you want to include and cpck Finish.
You will see that Entity model and POCO classes are generated from the database.
Let us now retrieve all the students from the database by writing the following code in program.cs file.
using System; using System.Linq; namespace DatabaseFirstDemo { class Program { static void Main(string[] args) { using (var db = new UniContextEntities()) { var query = from b in db.Students orderby b.FirstMidName select b; Console.WriteLine("All All student in the database:"); foreach (var item in query) { Console.WriteLine(item.FirstMidName +" "+ item.LastName); } Console.WriteLine("Press any key to exit..."); Console.ReadKey(); } } } }
When the above program is executed, you will receive the following output −
All student in the database: Ap Khan Arturo finand Bill Gates Carson Alexander Gytis Barzdukas Laura Norman Meredith Alonso Nino Opvetto Peggy Justice Yan Li Press any key to exit...
When the above program is executed, you will see all the students’ name which were previously entered in the database.
We recommend you to execute the above example in a step-by-step manner for better understanding.
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