1.NET Language Integrated Query Yishai Zaltzberg

2 Agenda:  Why LINQ?  What is LINQ  Code samples  Compare to code without LINQ  Simple query  Working with Xml  Aggregation  Join  Use SP  Etc.  Impact and performance.  Questions ?

3 Classic ADO.NET SqlConnection conn = new SqlConnection(“...“); SqlCommand cmd = conn.CreateCommand(); cmd.CommandText SELECT * FROM Vehicles WHERE Model “Mercedes“); SqlDataReader r = cmd.ExecuteReader(); while ( r.HasRows ) { Console.WriteLine(r[“Number"] + r[“Year"]); } SqlConnection conn = new SqlConnection(“...“); SqlCommand cmd = conn.CreateCommand(); cmd.CommandText SELECT * FROM Vehicles WHERE Model “Mercedes“); SqlDataReader r = cmd.ExecuteReader(); while ( r.HasRows ) { Console.WriteLine(r[“Number"] + r[“Year"]); } Application Relational Database No intellisence No compile time checks Untyped Results

4 XML Objects Relational Data

5 Samples

6 Simple Xml Build – Before LINQ

7 Simple Xml Build

8 Before LINQ

9 Build Xml from DB