LINQ for SQL SQL Saturday May 2009 David Fekke

Who am I? David Fekke davidfekke@gmail.com Software Engineer at LPS Reformed DBA/Sharepoint developer JaxFusion.org

LINQ Language Integrated Query

ORM or Object Relational Mapper

.NET 3.5 Framework

SQL vs. LiNQ

Abstraction

SQL Server 2005/8

MySQL PostgreSQL Other RDBMS supported by Open Source

Oracle Provider Through DevArt

IQueriable Interface

Query Objects Query XML Query Databases

var myQuery = from p in db.people where p.firstname == “David” select p

LINQ makes use .NET 3.5 language features

C# 3.0 VB .NET 9.0

Lamda Expressions Anonymous Types Dynamic Types

Pros and Cons Visual Studio Generates Object code No reason to create separate queries for each RDBMS Auto parametrize variables Use Stored Procedures No hinting careful about in memory querying SQL Statements are auto-generated with the exception of Stored Procs