Multi mapping in dapper.net

c# dapper

Question

I'm implementing my first Dapper.Net project. Now i'm wondering what's the easiest way to initialize an object that contains another object(multi mapping).

Here's my code:

public static IEnumerable<ShopPrefix> GetShopPrefixes(short fiSL)
{
    using (var con = new SqlConnection(Properties.Settings.Default.RM2Con))
    {
        const String sql = @"
            SELECT  locShopPrefix.idShopPrefix,
                    locShopPrefix.fiSL,
                    locShopPrefix.fiShop,
                    locShopPrefix.Prefix,
                    locShopPrefix.Active,
                    locShop.idShop,
                    locShop.ShopName,
                    locShop.ContactPerson,
                    locShop.Street,
                    locShop.ZIP,
                    locShop.City,
                    locShop.Telephone,
                    locShop.Telefax,
                    locShop.Email,
                    locShop.ShopKey
            FROM    locShopPrefix
                    INNER JOIN locShop
                        ON locShopPrefix.fiShop = locShop.idShop
            WHERE   (locShopPrefix.fiSL = @fiSL);";
        con.Open();
        IEnumerable<Tuple<ShopPrefix,Shop>> shops =
            con.Query<ShopPrefix, Shop, Tuple<ShopPrefix, Shop>>(
            sql
            , (shopPrefix, shop) => Tuple.Create(shopPrefix, shop)
            , new { fiSL = fiSL }, splitOn: "idShop"
        );
        foreach (var shop in shops)
            shop.Item1.Shop = shop.Item2;
        return shops.Select(t => t.Item1);
    }
}

So every shopPrefix belongs to (has) a Shop.

Q: Is this the correct way to map two objects since the Tuple approach with the following foreach to initialize the property Shop looks cumbersome?

Accepted Answer

I don't think you need a IEnumerable<Tuple<>> for a simple One-To-One object relationship. The following snippet should be sufficient as well.

var shopsPrefixes = con.Query<ShopPrefix, Shop, ShopPrefix>(sql
    , (shopPrefix, shop) =>
    {
        shopPrefix.Shop = shop;
        return shopPrefix;
    }
    , new { fiSL = fiSL }
    , splitOn: "idShop"
);
return shopsPrefixes;



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