LINQ TO SQL

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LINQ TO SQL

Prepared By: Nilesh R. Parmar

Introduction How LINQ works?

ArchitectureUnderline ExecutionExecution Mode

Why LINQ? LINQ to Objects LINQ to SQL Select in LINQ Insert in LINQ Update in LINQ Delete in LINQ

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Language Integrated Query

A set of language extensions that allows you to perform queries without leaving the comfort of the programming language (C# or VB)

Defines keywords that you use to build query expressions like select, from and where

Select, filter, sort, group or transforms the data

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

var contacts = from c in customers where c.State == "WA" select new { c.Name, c.Phone };

var contacts = customers .Where(c => c.State == "WA") .Select(c => new { c.Name, c.Phone });

Extension Extension methodsmethods

Lambda Lambda expressionsexpressions

Query Query expressionsexpressions

Object Object initializersinitializers

Anonymous Anonymous typestypes

Local Local variable type variable type inferenceinference

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Deferred Execution

var data = from d in ibEntity.Tourists

where d.IsIBMember == true select d;

inMemoryData = data.ToList();

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Immediate Execution

var city = ( from c in inMemoryData

select (c.City.ToUpper())

).Distinct();

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Unifies the way of accessing data from different data sources.

Compile-time checking of all queries, reduces run time errors.

Strongly typed.

Can be applied in any project layer (UI/Business/Data)

Extensive Intellisence/Debugging support.

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Query can be executed on collections & objects that implements IEnumerable interface.

LINQ queries Vs. foreach loops:

Concise and readable, especially when filtering multiple conditions.

Provides powerful filtering, ordering, and grouping capabilities with a minimum of application code.

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

Query data in the SQL Server Database

Implicitly transforms LINQ expression into a set of SQL queries

Advantages: Flexibility Change Tracking & Batch Updates Less code

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C

NicheTech Computer Solutions Pvt. Ltd Prepared By: Nilesh R. Parmar C