1. LINQ 2 SQL
By, Shahzad Sarwar

2. What you should know, before starting
Anonymous function
Anonymous type
Anonymous Methods
Lamda expression
Collection Initializers
Object Initializers
Extension methods
Type Inference
Automatic properties
Partial Methods
Generic
Projection (Later)
Expression Tree (Later)

3. What is the problem?
Class!=Data
1. strongly-typed queries , what ?
2. strongly-typed results
Benefits
1. IntelliSense
2. Compile-time error checking.

4. What r OR Mappers(OR/M)? Not ORM? What is Object Role Modeling (ORM)?
What is Linq to SQL?
1.OR Mapper API
2.Syntax to query ( LINQ to objects )
3.Tools
What r OR Mappers(OR/M)?
Not ORM?
What is Object Role Modeling (ORM)?
Associated language FORML (Formal Object-Role Modeling Language)
Supported by Visio and Microsoft Architect
References:

5. Current Solutions in market
.NET Persistence
BBADataObjects
DataObjects.NET
Data Tier Modeler for .NET
DotNorm
Eldorado.NET
Enterprise Core Objects (ECO™)
Entity Broker
eXpress Persistent Objects for .NET
FastObjects.NET
JC Persistent Framework
LLBLGen Pro
ModelWorks
Nhibernate
Nolics.NET

6. Current Solutions in market
Norm
Norpheme
ObjectBroker
ObjectSpaces
ObjectSpark
Objectz.NET
OJB.NET
OPF.Net (Object Persistent Framework)
ORM.NET
Pragmatier Data Tier Builder
RapTier
Sisyphus Persistence Framework
TierDeveloper
Bob.NET
ObjectPersistor.NET
Genome

7. A view of LINQ LINQ Consist of : LINQ to Objects
Total 6 LINQ implementations
3 general LINQ technologies
2 related to relational databases (OR/M)
1 Future Technologies
LINQ to Objects
Over objects , system.linq
LINQ to Dataset
over dataset ( LINQ to objects + system.data.dataextension )
LINQ to SQL- DLinq
Direct sql server ( system.data.linq )

8. LINQ to entities LINQ to XML = xlinq PLINQ
entities framework ( a part of the ADO.NET Entity Framework which allows LINQ query capabilities)
The Entity Data Model (EDM) is a conceptual data {System.data.entity}
LINQ to XML = xlinq
The low-level XmlReader/XmlWriter API in .NET today. {System.Xml.Linq}
PLINQ
Query execution engine accepts any LINQ-to-Objects or LINQ-to-XML query and automatically utilizes multiple processors or cores for execution when they are available.

9. Conceptual View (LINQ)

10. Conceptual View (LINQ to Dataset)

11. Conceptual View (LINQ 2 entities)

12. Conceptual View ( PLINQ)

13. References [LINQ to Dataset] [LINQ to entities]
[LINQ to entities]

14. What is difference LINQ to SQ L and LINQ to Entities?
1:1 vs many to many , complex mapping
sql only , any database .... so run in database specfic pattern.
Sample Application on the fly
Sample Application:
Sample Add , delete , edit
Example
What next ??????????????????????????? It is over…

15. DataContext Connection like class (Mixture of a lot of objects)
Caching n change tracking
Example
Log
ExecuteCommand
GetTable
ExecuteQuery
Refresh
ObjectTrackingEnabled
Transaction
Cases:
Nested Query
Cache Query / Multiple context
ToList()
What is Projection?

16. Context Management Four Approaches
1. Create a new Context for each atomic operation (Application level management)
Problem: pass data objects or the data context itself around to other components in your application.
E.g.: if you use business objects there's no real clean way to get a context passed between business objects.
2.Create a global DataContext and handle all operations against this single DataContext object
Problem:
In other words if you have multiple simulataneous data operations that might not be directly linked/atomic
Not possible to do simple update.....?
and Options such ObjectTrackingEnabled or DeferredLoadingEnabled can't be set easily
Works for desktop , not for Web because of threading

17. Context Management 3.Create a thread specific DataContext
Request specific DataContext that is tied to the active thread,Web request to the active ASP.NET HttpContext.
Example
Factory Pattern
4. Create a per business object DataContext

18. Architecture Guide Lines
References:

19. Code Generation 2 Options Code Understanding Explore
VS Studio OR Designer
SQLMetal
Code Understanding
Explore
XML Mapping file
Generated classes
dataConext ,Database, Table, relationships
Example

20. Query pipeline
LINQ 2 Objects = IEnumerable
LINQ 2 SQL= IQueryable
public interface IQueryable : IEnumerable {
Type ElementType { get; }
Expression Expression { get; }
IQueryProvider Provider { get; } }
What is Expression Tree?
a method of translating executable code into data.
Add-ons:
Query Visualizer
Expression Tree Visualizer
Example
Out of processor , Grammar , sql processor
Various Stages ( Out of scope )
1-Many mapping b/q LINQ grammer to db sql
References:

21. Joins n Lazy Loading Types of Joins Example
Inner Join
Left Outer Join
Right Outer Join
Cross Join
Example
LINQ implementation of Joins
Deferred Loading of objects
DataLoadOptions/DeferredLoadingEnabled property
AssociateWith Property

22. LINQDataSource Like sqlDataSource
Example 1 (Wizard View , declarative View )
Overriding events
Selecting event
Example 2

23. Using Store Procedure Add Store procedures to Model Example
Add function to Models
Difference b/w Store Procedure n function
for computations , for Business logic
Functions can be called inside select/update/delete stmt but not the procedures.

24. LINQ2SQL Customization
By Store Procedure
Example
Object validation (Partial classes)
Customize entity class ( 1 to m mapping )

25. Inheritance
In OR Mapping, 3 Type
Example

26. Table per Class Hierarchy
[Example]

27. Table per Subclass

28. Table per Concrete Class

29. LINQ Dev. Tools Visual LINQ Query Builder through a friendly interface
[Demo]
LINQPad
Development tool

30. Performance Benchmark 1 References

31. Performance Adventure Db , Store procedure
So, comparing to the raw ADO.NET - DAAB is 8% slower and LINQ is 28% slower. Comparing to DAAB - LINQ is 18% slower.
Reference:

32. Performance But consider Productivity
SQL being first class language in VS
Caching of DB.
Change tracking optimization
So Over a Great Milestone in Development process

33. What is Left……………….. Design Pattern for LINQ to SQL XLINQ
LINQ to Dataset
LINQ to entities
PLINQ
n…………………….
…..
…………..
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So Wait for Next presentation on LINQ …………………