Using LINQ to SQL Template – Part One

LINQ to SQL is an ORM (Object Relational Mapping) framework that allows you to work with databases using LINQ queries.

Setting Up LINQ to SQL

Add a new LINQ to SQL Classes item to your project (.dbml file)
Drag tables from Server Explorer onto the designer
The designer generates entity classes automatically

Basic Queries

csharp

using (DataContext db = new DataContext(connectionString))
{
    // Simple select
    var customers = from c in db.Customers
                    select c;
    
    // With where clause
    var filteredCustomers = from c in db.Customers
                            where c.City == "Sydney"
                            select c;
    
    // With ordering
    var orderedCustomers = from c in db.Customers
                           orderby c.Name ascending
                           select c;
    
    // Selecting specific columns
    var names = from c in db.Customers
                select new { c.Name, c.Email };
}

Method Syntax

csharp

var customers = db.Customers
    .Where(c => c.City == "Sydney")
    .OrderBy(c => c.Name)
    .Select(c => new { c.Name, c.Email });

Continue to Part Two for advanced queries and data manipulation.

Setting Up LINQ to SQL

Basic Queries

Method Syntax

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