Table of Contents

Name adaptation

Case insensitive names

public record Customer(int Id, string Name);

Customer customer = cnn.Query<Customer>("SELECT CustomerId AS ID, Name AS name FROM customers WHERE CustomerId = @customerId", new { customerId = 12 });
// ID fills Id.
// name fills Name.

SQL alias

public record Customer(int Id, string Name);

List<Customer> customers = cnn.Query<List<Customer>>("SELECT customer_id AS Id, display_name AS Name FROM customers");

Alt

public record Customer([Alt("customer_id")] int Id, [Alt("display_name")] string Name);

List<Customer> customers = cnn.Query<List<Customer>>("SELECT customer_id, display_name FROM customers");

The declared member name remains accepted alongside its alternate name.

External name mapping

public record Customer(int Id, string Name);

TypeParsingInfo.GetOrAdd<Customer>().UpdateAltName(names =>
    names.GetDefaultName() switch
    {
        "Id" => new NameComparer("customer_id"),
        "Name" => new NameComparer("display_name"),
        _ => null
    });

List<Customer> customers = cnn.Query<List<Customer>>("SELECT customer_id, display_name FROM customers");

SQL keeps customer_id and display_name. The CLR type keeps Id and Name. The registration carries the translation.

Paths compose with names

public record Address([Alt("Postal")] int Zip, string City) : IDbReadable;
public record Person(int Id, Address Home);

Person person = cnn.Query<Person>("SELECT PersonId AS Id, ZipCode AS HomePostal, City AS HomeCity FROM people WHERE PersonId = @personId", new { personId = 12 });
// HomePostal reaches Home.Zip through Alt("Postal").

The same process keeps going when the same type appears again.

public record Employee(int Id, string Name, [Alt("Boss")] Employee? Manager = null) : IDbReadable;

Employee employee = cnn.Query<Employee>("SELECT e.EmployeeId AS Id, e.Name, m.EmployeeId AS ManagerId, m.Name AS ManagerName, b.EmployeeId AS ManagerBossId, b.Name AS ManagerBossName FROM employees e LEFT JOIN employees m ON m.EmployeeId = e.ManagerId LEFT JOIN employees b ON b.EmployeeId = m.ManagerId WHERE e.EmployeeId = @employeeId", new { employeeId = 12 });
// ManagerBossId reaches employee.Manager.Manager.Id.

Recursive mapping · Construction paths

Skip fixed path segments

public record Inner([AltSkippingSegments("Code", 2)] int Code) : IDbReadable;
public record Middle(Inner Sub) : IDbReadable;
public record Outer(int Id, Middle Mid);

MidSubCode    complete path
MidCode       accepted alternate path

Skip through a named path segment

public record LayerTwo([AltUpTo("NotTooDeep", "Two")] int Second, LayerThree Three) : IDbReadable;
public record LayerThree([AltUpTo("SuperDeep", "Two")] int Third) : IDbReadable;

AltUpTo changes the accepted path through the named segment.

AltUpTo API

No name match

public readonly record struct Boxed<T>([NoName] T Value);

Boxed<int> value = cnn.Query<Boxed<int>>("SELECT COUNT(*) FROM albums");

[NoName] accepts the next compatible column without matching a column name.

Reading order · Type registration

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