What is the syntax for an inner join in LINQ to SQL?

Crafting Results with Anonymous Objects

Craft concise queries and customized results using anonymous objects:

from product in context.Products
join sale in context.Sales on product.ID equals sale.ProductID
select new { product.Name, sale.Date, sale.Quantity }; // Voila! You handpicked the result!
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You can also tap into navigation properties as a breather from join. Here, Product is a subentity of the Sale class:

from sale in context.Sales
select new { sale.Product.Name, sale.Date, sale.Quantity }; // look Ma, no joins!
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Multi-condition Joins: Double the Fun!

&& operator comes handy when you yearn to constrain on multiple fields:

from c in context.Customers
join o in context.Orders on c.ID equals o.OrderID && c.Region equals o.ShipRegion
select new { c.Name, o.OrderDate }; // i.e. find me customers who forgot their orders in the same region!
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Turbocharged Joins with .Join() Method

To add more fine-grain control and readability, choose the .Join() method:

context.Customers
.Join(context.Orders,
      customer => customer.ID,
      order => order.CustomerID,
      (customer, order) => new { customer.Name, order.OrderDate }); // That's some lambda magic right there!
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Query Optimization Toolkit

Pin-point Projections

While sculpting your select statement, sieve out the gems for leaner data:

select new { c.Name, c.Email, o.TotalAmount }; // I want only these! No more, no less.
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Lay Back with Deferred Execution

Use the lazy (but smart) way with deferred execution. LINQ queries don't rush to execute, perfect for late refinements:

var query = from c in context.Customers
            join o in context.Orders on c.ID equals o.CustomerID
            select new { c, o };

// ... Anytime later
var filteredQuery = query.Where(c => c.o.TotalAmount > 100).ToList(); // snooze anda execute!
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Sense-making with Enumerations

Decode your integers with enumerations for relevance and readablility in results:

select new { Status = (OrderStatus)o.Status, o.OrderDate }; // Who knew 1 meant 'In Progress' all this while?
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