Introducing Entity Framework

EF v1.0

History of ADO.Net

Object Relational Mapping {ORM}

What is Entity Framework?

Entity Framework Architecture

Entity Data Model {EDM}

Entity Client & Object Services

LINQ to Entities & Entity SQL {eSQL}

Agenda

Load Related Objects

Inheritance in Entity Framework

Entity Framework providers and multiple database support

Entity Framework Limitations

External Tools

References

Agenda (Cont.)

History of ADO .Net

•Object Oriented Datasets.

•Disconnected Model.

•Provider Abstraction.

2002ADO .Net v1.0

•Provider Factories•Metadata schema•Asynchronous Command Execution

•Conflict Detection•Batch Updates•Multiple Active Result Sets (MARS)

2005ADO .Net v2.0

•Nothing changed in ADO.net

2006ADO .Net v3.0

•Paging Support

•Synchronization APIs

•Language integrated Query (LINQ)

•LINQ to SQL

2007ADO .Net v3.5

•Entity Data Model (EDM)•Object Services•LINQ to Entities•Entity SQL•Entity Client•ADO .Net Data Services

2008ADO .Net v3.5

SP1

Object Relational Mapping

{ORM}

Definition

ORM & Visual Studio

External Tools & frameworks for .Net

ORM Basics & Concepts

What is Entity Framework?

Why it is considered an ORM?

What is Entity Framework?

An ORM framework, Why?

Database Independent

Extensible

Part of Microsoft .Net framework 3.5 SP1

Getting Started

Demo

Entity Framework Architecture

Entity Framework Architecture

Entity Data Model (EDM)

What is Entity Data Mode?

SSDL

MSL

CSDL

Entity Data Model (EDM)

EDM in Action

Demo

Entity Client & Object Services

Entity Client EntityClient Provider for Entity Framework

System.Data.EntityClient

Abstracts DBMS Providers for Entity Framework Architecture

Entity Client in Action

Demo

Object Context

Entity Contain

er

Object Services

Entity Connection

Object Services

Object Services in Action

Demo

Break (30 minutes)

LINQ to Entities & Entity SQL

LINQ to Entities What is LINQ

◦ LINQ to Objects◦ LINQ to XML◦ LINQ to DataSets◦ LINQ to SQL◦ And more E.g. (LINQ to Twitter, LINQ to Flickr

etc…)

LINQ to Entities

LINQ to Entities in Action

Demo

Entity SQL (eSQL)

Supported NOT Supported

SQL based

Provider neutral

Supports EDM types

First class collections

Canonical functions

DML statements (insert,

update, delete)

DDL statement (create,

alter, drop)

Grouping functions (CUBE,

ROLLUP, GROUPING_SET

Does not support the *

construct

Entity SQL in Action

Demo

Entity SQL Vs LINQ to Entities

Dynamic queries (LINQ is compiled)

Store Function/Procedures is only supported in eSQL

Load Related Objects

Entity relation mapping (one to one, one to many, many to many)

Deferred Loading Vs Eager Loading Vs Explicit Loading

ObjectQuery<T> Class

EntityCollection<T> Class

EntityReference Class

Load Related Objects

Load Related Objects in Action

Demo

Inheritance in Entity Framework

Inheritance in Entity Framework

Table-per-Hierarchy (TPH) Table-per-Type (TPT)

Table

Hierarchy

Table

Type

One table in storage to maintain data for all the types in an inheritance hierarchy.

Table-per-Hierarchy (TPH)

Separate table in storage to maintain data for each type in the inheritance hierarchy.

Table-per-Type (TPT)

Inheritance in Action

Demo

Entity Framework Providers

Multiple database support

Entity Framework Providers◦ MySQL Connector\net (MySQL)◦ Devart (Oracle, MySQL, SQLite and PostgreSQL)◦ IBM (DB2, Informix and U2 databases)◦ Phoenix Software Solutions (SQLite)◦ Npgsql (PostgreSQL)◦ Sybase SQL Anywhere (SQL Anywhere 11)◦ Firebird (Firebird)◦ VistaDB (VistaDB 4.x)

Multiple Database Support in Entity Framework

Multiple Database Support

Demo

Entity Framework Limitations

Known Issues and Considerations in LINQ to Entities◦ Ordering Information Lost◦ Nested Queries. Nested Queries May Fail with SQL

Server 2000◦ Unsigned Integers Not Supported◦ Enums not supported◦ Referencing Non-Scalar Closures Not Supported◦ Custom extension methods Not Supported◦ Some common sense methods not supported

(Single, SingleOrDefault)

Entity Framework Limitations

Entity Framework VS.Net Designer Limitations

limitations in Entity SQL◦ DDL not supported◦ DML not supported (insert, update, delete)

Design issues◦ No Persistence Ignorance support a.k.a POCO◦ Leakage of Testability

I am sure there might be more

Entity Framework Limitations (Cont.)

LINQPad eSQLBlast

◦ http://code.msdn.microsoft.com/esql/

External Tools

References

MSDN◦ Programming Guide (Entity Framework)◦ Load Related Objects (Entity Framework)◦ Inheritance in Entity Framework

TPH TPT

◦ Known Issues and Considerations in LINQ to Entities

◦ Entity Framework and LINQ to Entities Forums◦ ADO.NET Entity Framework and LINQ to Entities (P

re-Release) Forums

References

Community◦ Zeeshan Hirani Entity Framework Learning Guide

Post PDF

◦ Gil Fink on Entity Framework◦ Moses’ blog on Entity Framework◦ Entity Framework Supported Mapping Scenarios

White Paper by Asad Khan

References (Cont.)