(Yet Another) .Net object-relational mapper

Norm is an opinionated object-relational mapper (ORM). It relies on a specific set of naming conventions for your objects. Yes, strict adherence to an arbitrary set of naming conventions limits the range of use cases that Norm can handle, but I was scratching my own itch, and wanted a simple ORM for smaller projects that does only what I need it to, and doesn't require a bunch of setup to get started.

Norm defines a single class for interacting with your database, aptly named Database. You have 2 options for initializing a Database object:

// Pass in the connection string. Norm will open a connection to the database, and close it when it's done.
public Database(string connectionString)

// Pass in the connection. Norm will assume the connection is already open, and leave it open when it's done.
public Database(IDbConnection connection)

The Database class defines 4 methods for performing your typical CRUD database operations: Select, Insert, Update, Delete.

The Select method builds a query using a fluent-interface. You can then return a single object using SingleOrDefault(), or a list of matching objects using ToList(). The query can be fine-tuned using a number of fluent methods: OrderBy(), OrderByDesc(), and Limit().

Example usage:

public class Person
{
    public int Id { get; set; }
    public string FirstName { get; set; }
	public char MiddleInitial { get; set; }
	public string LastName { get; set; }
	public char Gender { get; set; }
	public DateTime CreateDate { get; set; }
	public DateTime? UpdateDate { get; set; }
}

var db = new Norm.Database(connString);

// select all
IEnumerable<Person> people = db.Select<Person>().ToList();

// select one
Person person = db.Select<Person>(p => p.Id == 1).SingleOrDefault();

// use of OrderBy and Limit
IEnumerable<Person> people = db.Select<Person>(p => p.LastName == "Smith")
                               .OrderBy(p => p.FirstName)
                               .Limit(5)
                               .ToList();

The Insert method inserts the object obj, and returns the Id of the newly inserted object.

Example usage:

Person person = new Person();
person.FirstName = "John";
person.MiddleInitial = 'Q';
person.LastName = "Smith";
person.Gender = 'M';

person.Id = db.Insert(p);

The Update method updates an existing object obj, and returns true if the object was updated successfully, otherwise false.

Example usage:

Person person = db.Select<Person>(p => p.Id == 1).SingleOrDefault();
person.FirstName = "Jane";
person.MiddleInitial = null;
person.LastName = "Doe";
person.Gender = 'F';

db.Update(person);

The Delete method deletes an existing object obj, and returns true if the object was deleted successfully, otherwise false.

Example usage:

Person person = db.Select<Person>(p => p.Id == 1).SingleOrDefault();
db.Delete(person);

• Norm assumes that your object and property names map directly to your table and column names.
• Norm uses the following naming conventions (note that name-matching is not case sensitive):
  • The primary key field (required) is either Id or <TypeName>Id.
  • The created timestamp (optional) is either Created, CreateDate, or CreatedOn. This field will automatically be set when a record is inserted.
  • The updated timestamp (optional) is either Updated, UpdateDate, or UpdatedOn. This field will automatically be set when a record is updated.