1. Accessing Data in a .NET Web Application
Shyam Pather
Development Manager
Data and Modeling Group – Microsoft

2. Agenda .NET Data Access basics for the Web
MVC, Repositories, and POCOs
Using Models: Entity Framework and EDM
Accessing OData

3. Demo: .NET Data Access basics

4. Demo Recap ADO.NET basic patterns
using (connection) { … }
connection.CreateCommand()
command.ExecuteReader()
Connection strings managed in Web.config
Simple, streaming access to data

5. Where should data access go?
M, V, C is about separation of concerns
Data Access goes in model layer
Use the repository pattern to hide data access details
Use POCO / “Persistence Ignorant” data classes
Controllers consume repository
Views consume POCO model classes
Controller
Action Methods
View
HTML
Model
Repository + POCOs

6. Where do we get our POCOs?
Definition of POCO classes
Hand-written classes
(Later) Code generation
Instantiation of POCO classes
“By hand” from DataReader results
Automatically, using ExecuteStoreQuery<T>

7. Demo: MVC, Repositories, POCOs

8. Demo Recap Same basic ADO.NET patterns but hide the details
Use repository pattern
Repositories return POCOs
Consumed by the controller
Bound to the View
ExecuteStoreQuery<T>
Easiest way to get objects from query results

9. Using Models Entity Data Model lets you describe your data
Entities with Relationships
Complex types, inheritance, navigations etc.
Mapping to database
Entity Framework gives you CRUD over your model
LINQ querying, POCOs for results
Change tracking, updates
You can get other services too…
E.g. WCF Data Services provides OData head

10. Creating Models Start with the database Start with an edmx model
“Database is the truth”
Why? It already exists, or you want low level control over the database
What? Import model into edmx and tweak
Walkthrough: This talk
Start with an edmx model
“Edmx is the truth”
Why? You want separation from code and database in a declarative format
What? Create a model in the designer
Walkthrough:
Start with .net classes
“Code is the truth”
Why? Primarily focused on code shape, database is an implementation detail
What? Define classes in code, adjust shape using contextbuilder
Walkthrough:

11. Demo: Using Models

12. Demo Recap 3 ways to create an EDM
From database
On the design surface
With code
Entity Framework provides rich data access over EDM
E.g. LINQ, lazy loading, change tracking
T4-based code generation
Using EDM gives you other services e.g. OData head
Use WCF Data Services

13. What is OData? Uniform way of representing structured data
Atom, JSON formats
Uniform URL conventions
Navigation, filtering, sorting, paging, etc.
Uniform operations
Addressability
GET, POST, PUT, DELETE always mean the same
A growing number of services and clients
Servers: OGDI, NetFlix, Reporting Services
Clients: .NET, AJAX, PHP, Excel

14. Consuming OData Services
On .NET
Use Add Service Reference (generates proxy classes)
WCF Data Services client library
Uses patterns similar to Entity Framework
Supports LINQ querying
Fits easily into the repository pattern
Many other clients for other platforms

15. Demo: OData Access

16. Demo Recap Add Service Reference generates OData proxies
Similar patterns to Entity Framework
LINQ, Change Tracking etc.
Use the repository pattern!

17. Call to Action Explore your data access options in .NET
Visit
Try out the .NET 4 / VS2010 RC
Learn more about OData

18. Don’t forget… Please fill out an evaluation! Session Code: FT 15
Send questions to:

19. 11/27/2018 7:29 PM
© 2009 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

20. 11/27/2018 7:29 PM
© 2010 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.
© 2009 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.