This document discusses databases and data access in .NET. It covers database engines, ADO.NET, SQL Client for connecting to SQL Server, transactions and isolation levels. Object-relational mapping (ORM) frameworks like Entity Framework and LINQ to SQL are presented as alternatives to directly working with databases that map objects to relational data. Entity Framework's design approaches and capabilities like mapping, querying data, and inheritance strategies are demonstrated.

1. Databases in .NetVictor HaydinEleks Software Ltd.

2. Data and DatabasesComputer science is not about computing. Its about data processing.

3. Database engines

4. Application/DB interactionFrontend ServerPresentation LayerBusiness Logic LayerData Access LayerDatabase driversDatabase Server

5. ADO.Net

6. System.Data.SqlClientSystem.Data.SqlClient – set of classes for low-level operations with MS SQL Server.

7. demoSQL Client

8. Transactions & Isolation levels

9. Isolation levelsRead IssuesLocks

10. ORM

11. Why ORM?Relational Model:TablesRowsColumnsPrimary/Foreign keys?Object Model:CollectionsObjectsPropertiesCompositionInheritance

12. ORM FrameworksEntity FrameworkLINQ2SQLNHibernateDevExpress XPOSubsonicObjectMapper.NetSelf-made

13. ADO.Net Entity FrameworkDesign approaches:Database First

14. Model First

15. Code FirstEntity Data Model:Mapping

16. Entities