请问VS2012自带的SQL如何使用？

using (SqlConnection cn = new SqlConnection())
{
//VS2012 自带的SQL为 localdb,连接字符串有一点点不一样，其他功能都一样操作
cn.ConnectionString = @"data source=(localdb)\v11.0;Initial Catalog=C:\DATA\APPLICATIONDATABASE.MDF;integrated security=True;connect timeout=120";
cn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = cn;
cmd.CommandText = "select * from table";

SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
return ds;
}