LINQ i alla dess smaker

1. LINQ i alla dess smaker Johan Lindfors blogs.msdn.com/johanlJohan.Lindfors@microsoft.com Patrik Löwendahl www.lovendahl.netPatrik.Lowendahl@cornerstone.se

2. Bakgrund och utmaningar

4. Message Object Domain Model XML Data Transfer Object Active Record DataTable DataSet Objekts modell Repositories DataReader

5. !

6. ADO.NET

7. DataSet DataTable DataTable

9. SQL Server 2005 SQL Server 6.5 Categories Products Customers Orders SqlDataAdapter OleDbDataAdapter DataSet Categories Products Employees Customers Orders XmlDataDocument XML Fil Web service

10. För- och nackdelar

11. Domänmodeller

12. Fokus på applikation inte lagring Frikopplar affärslogik från datastrukturen Större möjligheter till återanvändning och utökningar

16. För- och nackdelar

17. LINQ

18. LINQ-projektet <book> <title/> <author/> <year/> <price/> </book> Relationer Objekt XML .NET Language Integrated Query C# 3.0 Visual Basic 9.0 Andra… LINQ toObjects LINQ toDataSets LINQ toSQL LINQ toEntities LINQ toXML

19. Nyheter i C# 3.0 “Query expressions” var contacts = from c in customers where c.State == "WA" select new { c.Name, c.Phone }; “Local variable type inference” “Lambda expressions” var contacts = customers .Where(c => c.State == "WA") .Select(c => new { c.Name, c.Phone }); “Extension methods” “Anonymous types” “Object initializers”

20. LINQ to SQL

21. Designmål Direkt mappning mot SQL RAD ”Deferred Execution” Mål: Microsoft SQL Server RTM: Visual Studio 2008

25. Anpassning av affärslogiken Partiella klasser och metoder Lagrade procedurer Optimering Kompilerade frågor

26. LINQ to Entity Framework

27. Koncept vi skall beröra Mappning Att ställa frågor Updatera data Stored procedures Arkitektur

28. Mappning

29. Källa: www.endintiers.com

30. Conceptual Model Map Storage/Logical Model Entity Data Model Schema Datastore Objects Schema *.CSDL *.MSL *.SSDL Datastorage OO Classes

32. Att ställa frågor

33. ObjectQuery<T> ObjectContext EntityDataReader EntityCommand EntityConnection EntityDataReader EntityCommand EntityConnection Database

34. EF Stored Procs & TVFs Entity SQL Queries Normalised Application Objects Views Database LINQ to Entities Queries ‘Optimised’ Dynamic SQL

35. LazyLoad Källa: www.martinfowler.com

36. Load spans

37. Identitymap Källa: www.martinfowler.com

38. Uppdatera data

39. ObjectContext UnitOfWork

41. Stored procedures

42. Functionmapping SSDL: <Function Name="TenMostExpensiveProducts" Aggregate="false" BuiltIn="false" NiladicFunction="false" IsComposable="false” ParameterTypeSemantics="AllowImplicitConversion" Schema="dbo" /> CSDL: <FunctionImport Name="TenMostExpensiveProducts" EntitySet="Products" ReturnType="Collection(NorthwindEFModel.Products)" /> MDL: <FunctionImportMapping FunctionImportName="TenMostExpensiveProducts” FunctionName="NorthwindEFModel.Store.TenMostExpensiveProducts"/> Context: var query = context.TenMostExpensiveProducts();

43. Insert / Update / Delete SSDL: <Function Name="CreateCategory" IsComposable="false”> <Parameter Name="CategoryName" Type="nvarchar" /> </Function> <Function Name="EditCategory" IsComposable="false"> <Parameter Name="CategoryID" Type="int" /> <Parameter Name="CategoryName" Type="nvarchar" /> </Function> <Function Name="RemoveCategory" IsComposable="false"> <Parameter Name="CategoryID" Type="int" /> </Function> MDL: <ModificationFunctionMapping> <InsertFunction FunctionName="dbo.CreateCategory”> <ScalarProperty Name="CategoryName” parameterName="CategoryName" /> <ResultBinding ColumnName="CategoryID" Name="CategoryID"/> </InsertFunction> <UpdateFunction FunctionName="dbo.EditCategory”> <ScalarProperty Name="CategoryID” ParameterName="CategoryID” Version="current"/> <ScalarProperty Name="CategoryName” ParameterName="CategoryName” Version="current"/> </UpdateFunction> <DeleteFunction FunctionName="dbo.RemoveCategory”> <ScalarProperty Name="CategoryID” ParameterName="CategoryID"/> </DeleteFunction> </ModificationFunctionMapping>

44. Arkitektur

45. SQL Server Relational DBMS Applications Programming Layers Code Gen • XML • XLinq • XQuery • Objects • Linq … Browsing Binding Entity Client – EDM, Entity SQL Domain Modeling Tools Metadata Services Query and Update Pipelines Mapping Mapping Entity Framework Runtime Transactions Modeling Data Providers (ADO.NET patterns) SqlClient OtherClient Non-relational Web Service

46. Läs mer… http://forums.msdn.com http://msdn.microsoft.com/data http://www.lowendahl.net http://blogs.msdn.com/adonet http://forum.cornerstone.se http://blogs.msdn.com/angelsb

47. LINQ to DataSet

48. ”Disconnected cache” Otypade var query = from row in myDataSet.Tables["Customers"].AsEnumerable() where row .Field<string>("City") == "London" select new { row.Field <string> ("CustomerID"), row.Field <string> ("ContactName") } ; Typade var query = from customer in northwind.Customers where customer.City == "London" select customer;

49. LINQ to XML

50. ”Astoria”