public uint NumberOfPurchases(UUID UserID)
{
QueryFilter filter = new QueryFilter();
if (UserID != UUID.Zero)
filter.andFilters["PrincipalID"] = UserID;
var purchases = GD.Query (new string[] { "count(*)" }, _REALMPURCHASE, filter, null, null, null);
if ((purchases == null) || (purchases.Count == 0))
return 0;
return (uint)int.Parse (purchases [0]);
}