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c#.netservicestackormlite-servicestack

Querying POCO's with References


I have the following (simplified) datamodel:

public class Order : IHasId<long>
{
    [AutoIncrement]
    public long Id { get; set; }

    [References(typeof(Material))]
    public long MaterialId { get; set; }

    [Reference]
    public Material Material { get; set; }
}

public class Material : IHasId<long>
{
    [AutoIncrement]
    public long Id { get; set; }

    public string Name { get; set; }
}

What I want to achieve is to populate Order.Material with the material referenced by MaterialId, is there a way to achieve that in a simple way? The Load APIs seem to do something similar, but in the inverse situation (when the reference is on Material, not on Order)


Solution

  • This is called Self References in OrmLite and works with your above example:

    public class Order : IHasId<long>
    {
        [AutoIncrement]
        public long Id { get; set; }
    
        [References(typeof(Material))]
        public long MaterialId { get; set; }
    
        [Reference]
        public Material Material { get; set; }
    }
    
    public class Material : IHasId<long>
    {
        [AutoIncrement]
        public long Id { get; set; }
    
        public string Name { get; set; }
    }
    
    db.Insert(new Material { Name = "A" });
    db.Insert(new Material { Name = "B" });
    
    db.Insert(new Order {
        MaterialId = 2,
    });
    
    var order = db.LoadSingleById<Order>(1);
    
    order.PrintDump(); 
    

    Recursively print object graph to Output:

    {
        Id: 1,
        MaterialId: 2,
        Material: 
        {
            Id: 2,
            Name: B
        }
    }