1. Lushanthan S.
getting started with Microsoft
Entity Framework

2. Today’s Agenda
 Introduction
 The Architecture
 Entity Data Model
 The Conceptual Model – .edmx file, exploring the classes
 Demo
 LINQ to Entities
 Lazy Loading
 CRUD
 Stored Procedures
 Shipped Products

3. Our life so far…
All of us have worked on Data access!
Objects != Relational Data – “Impedance mismatch”
Introduction
Languages C# SQL
Tools Visual Studio SQL Server
Paradigms Object Procedural
Common API ADO.NET
Powerful, but fragile and time consuming!

4. Legacy ADO.NET
Sample Code:
using (SqlConnection conn = new SqlConnection("<conn string>"))
{
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.CommandText = "sp_StoredProc";
cmd.parameters.AddWithValue("@City", "Colombo");
using (SqlDataReader rdr = cmd.ExecuteReader())
{
while (rdr.read())
{
Introduction
string name = rdr.GetString(0);
string city = rdr.GetString(1);
}
}
}
Loosely typed!

5. microsoft giving this to us as a
What about
Product?
Yes, there comes Microsoft Entity Framework

6. History of Data Access in .Net
ADO.Net Inline SQL
Data Sets
Stored Procedures
ORM - Typed Data Sets, LINQ to SQL, EF1, EF4
Introduction
Bridging the gap between objects and relational data!

7. What is Entity Framework?
Released in July 2008, EF is a data access framework from
Microsoft that helps to bridge the gap between data structures
and objects in your applications.
What does it really do?
It automatically,
Introduction
 generates strongly-typed entity objects that can be
customized beyond 1-1 mapping
 generates mapping/plumbing code
 translates LINQ queries to database queries
 materializes objects from data store calls
 tracks changes, generating updates/inserts

8. The Architecture Under the hood

9. Bird’s Eye View
Entity Framework
LINQ to Entities, Entity SQL, Query
builder methods
Programming
ADO.NET Entity Provider (entity client) Model
The Architecture
Conceptual Data Model
Legacy ADO.NET does not go away!
ADO.NET Data Provider
(SqlClient, OracleClient)
Reader Connection
Store
Adapter Command

10. Entity Data Model
Set of objects that describe structure of your business
data and map to your underlying data store.
Contained in Three XML sections stored in *.edmx file:
Entity Data Model
Database Entity
Schema Objects
Storage Model Mapping Conceptual Model
Database UI OO Services

11. The Conceptual Model The Conceptual Model

12.  Exploring the conceptual
model
 Database First
 Model First
 LINQ to Entities
 CRUD
 Lazy Loading
Demo  Include()
Following sections will be covered  Stored Procedures
.
.

13. Shipped Products
 Entity Framework 1.0 (.NET 3.5 SP1/ VS 2008 SP1 )
 Entity Framework 4.0 (.NET 4/ VS 2010 )
• Model-First support
• Foreign Keys in the conceptual Model
Shipped Products
• Lazy loading
• Persistence-Ignorant Objects (POCO) support
• Self-Tracking Entities
 Entity Framework 4.1, 4.2, 4.3 (.NET 4/ VS 2010 )
• Code-first Migration
 Entity Framework 5.0 beta1, 2 (.NET 4.5 Beta/ VS 2011 Beta )
• Enum support
• Tabled valued functions support

14. Linq to SQL Vs Entity Framework
L2S
Strongly typed LINQ access for RAD against SQL Server only
Support s only direct Table-Per-Type (1-to-1) mapping
Limited out-of-the box support for complex scenarios
EF
Designed for larger enterprise applications
Enables complex mapping complex scenarios
Tools and designer more robust
Supports inheritance and many-to-many relationships
Supports provider independence
14

15. ?
But wait…
There’s More!

16. Areas not covered
 POCO Entities
 Entity SQL
 T4 Templates
 Code first Approach
16

17. The End
Microsoft
Entity Framework
Q & A Session