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 private StockTicker(IHubConnectionContext<dynamic> clients)
    {
        Clients = clients;

        //Posts
        var mapper = new ModelToTableMapper<Posts>();
        mapper.AddMapping(s => s.ID, "ID");

        _tableDependency = new SqlTableDependency<Posts>(
            ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString,"tbl_Posts",
            mapper);

        _tableDependency.OnChanged += SqlTableDependency_Changed;
        _tableDependency.OnError += SqlTableDependency_OnError;
        _tableDependency.Start();
    }

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