UnderStanding ADO.NET Entinty Framework

by Erik Thompson -- ereckt@microsoft.com
Why the Entity Model
- Bridge Gap between OOP and relational databases
- Complex Types
- Your Data Model is not tightly bound to your DB
Creating Model
- EDM is represented as XML
- Use Ado Entity Designer -in vs2008 sp1
- Start Blank or from a Database
- Supports Many- to -Many relationships
- Entity Framework Requires 3 artifacts
- Model -CSDL
- Definition of Store - SSDL
- Mapping between the 2 - MSL
Programming Against it
- Enity Types
- CLR versions of EDM entities generallt generated by Tools
- Object Services
-LINQ
- Used to query against the generated classes
- Entity SQL
-SQL Variant for working in EDM
-String based not SQL
- Always keep entities attached to Object services
- Relationships are single worst stumbling blocks of EDM