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Setup database connection

In general, all database operations are performed on a StorageContext object. A StorageContext object needs a DataProvider which is specific to the type of database you're using.

var dbContext = new StorageContext(new SqliteDataProvider("my.db"));

// store dbContext somewhere

All database providers also have a dedicated Context class that you can use:

var dbContext = new SqliteContext("my.db");

In general, any database operation performed on a table needs to go through dataset (IDataSet<T>), which is an immutable object. To get a dataset for a context, call the DataSet<T>() method, where T is the type of the object:

var customer = dbContext.DataSet<Customer>().Read(1);

To work with single objects, you don't actually need a DataSet, but you can call methods on the StorageContext directly:

var customer = dbContext.Read<Customer>(1);
//
dbContext.Insert(customer);
//
dbContext.Delete(customer);

A dataset is a zero weight immutable object so there's no penalty in calling DataSet every time, but it's not very readable so it may be better to store the dataset objects for later use:

var dbCustomers = dbContext.DataSet<Customer>();
var dbOrders = dbContext.DataSet<Order>();
var dbProducts = dbContext.DataSet<Product>();

// You can use those datasets many times as they are immutable:

dbCustomers.Insert(new Customer { ... });
var someCustomers = dbCustomers.Where(...);

But there's a better way:

Subclassing StorageContext

You can derive your own context class from StorageContext and let Iridium create all the datasets for you:

public class MyContext : SqliteContext
{
   public MyContext() : base("my.db") {}

   IDataSet<Customer> Customers; // will be assigned automatically
   IDataSet<Order> Orders;       // will be assigned automatically
   IDataSet<Product> Products;   // will be assigned automatically
}

var db = new MyContext();

var customer = db.Customers.Read(1);

Static context

If you prefer to have your context and datasets available as static fields, you can do something like this:

public static class App
{
   public class MyDBContext : SqliteContext
   {
      public MyContext() : base("my.db") {}

      IDataSet<Customer> Customers;
      IDataSet<Order> Orders;
      IDataSet<Product> Products;
   }

   public static MyContext DB = new MyDBContext();
}

public void Main()
{
    Console.WriteLine("We have {0} customers in the database",
                 App.DB.Customers.Count()
              );
}
Copyright © 2015-2017 Philippe Leybaert