Re: online lottery system

[Huu Da Tran]

Eventhough in case 1, your ordering is not important, you might want to know in statistical views how many times a given number was drawn first, etc...

So if you get a table like:

Case 1:

mysql> create table `tc` (`drawID` int, `order` int, `number` int,
    ->   unique index `drawOrder` (`drawID`, `order`),
    ->   unique index `drawNumber` (`drawID`, `number`));
mysql> create view `vc` as
    ->   select `drawID`, group_concat(`number` separator '') as 'combination'
    ->     from `tc`
    ->     group by `drawID`
    ->     order by `number` asc;

Case 2:

mysql> create table `tn` (`drawID` int, `order` int, `number` int,
    ->   unique index `drawOrder` (`drawID`, `order`));
mysql> create view `vn` as
    ->   select `drawID`, group_concat(`number` separator '') as 'combination'
    ->     from `tn`
    ->     group by `drawID`
    ->     order by `order` asc;

Hope this is a good start,
H.