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 .Net Victor Haydin Eleks Software Ltd.

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

3. Database engines

4. Application/DB interaction Frontend Server Presentation Layer Business Logic Layer Data Access Layer Database drivers Database Server

5. ADO.Net

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

7. demo SQL Client

8. Transactions & Isolation levels

9. Isolation levels Read Issues Locks

10. ORM

11. Why ORM? Relational Model: Tables Rows Columns Primary/Foreign keys ? Object Model: Collections Objects Properties Composition Inheritance

12. ORM Frameworks Entity Framework LINQ2SQL NHibernate DevExpress XPO Subsonic ObjectMapper.Net Self-made

14. Model First

16. Entities

17. Relationships

19. LINQ to Entities

21. Table per type

23. Canonical Functions

24. Q&A