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POWhat is the standard pattern to retrieve JOINed data from normalized tables?
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  1. POWhat is the standard pattern to retrieve JOINed data from normalized tables?
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    copied!<p>I have the following simple "textbook" classes defined:</p> <pre><code> public class Product { public int Id { get; set; } public string Name { get; set; } public int Category { get; set; } } public class Category { public int Id { get; set; } public string Name { get; set; } } </code></pre> <p>The Category field in Product is an integer referencing the Id field in the Category class. In the database, it would be a foreign key relationship between the Product and Category tables.</p> <p>But my application would need to show the friendly name of the Category of a product.</p> <p><strong>Q1</strong>: Is it correct practice to define a new class as follows:</p> <pre><code> public class ProductJ : Product { public string CategoryName { get; set; } } </code></pre> <p>And then, if I now have a method getProductsJ as follows:</p> <pre><code> public class Test { public List&lt;Category&gt; Categories = new List&lt;Category&gt;() { ... }; public List&lt;Product&gt; Products = new List&lt;Product&gt;() { ... }; public List&lt;ProductJ&gt; getProductsJ() { var products = from p in Products join c in Categories on p.Category equals c.Id select new ProductJ { Id = p.Id, , Name = p.Name, CategoryName = c.Name }; //! return products.ToList(); } } </code></pre> <p><strong>Q2</strong>: Is the above the best way to retrieve a list of Products with Category names?</p> <p><strong>Q3</strong>: In the select statement (//!) is there a faster way to populate the fields of the base class Product linqwithout having to enter them one by one?</p> <p>Thanks.</p>
 

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