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Card Deck Simulation

  • October 17, 2004 at 9:15 pm

    #59630

    Does anybody have the code to simulate the random shuffling of 1 deck of cards?

  • October 17, 2004 at 11:06 pm

    #527000

    In what format do you want the results presented? Random order of numbers 1-52 in a table?

    Regards

    Phil

    If you haven't even tried to resolve your issue, please don't expect the hard-working volunteers here to waste their time providing links to answers which you could easily have found yourself.

  • October 18, 2004 at 2:20 am

    #527008

    An easy way to generate a 'random' sequence is to order by NEWID()

    Here's showing the principle:

    create table #deck ( card int not null )

    declare @i int

    set @i = 1

    while @i < 53

     begin

      insert #deck select @i

      set @i = @i + 1

     end

    -- deal a hand

    select top 5 card from #deck order by newid()

    -- shuffle whole deck

    select card from #deck order by newid()

    /Kenneth

  • October 18, 2004 at 6:48 am

    #527014

    Alternatives to Kenneth's

    select number

    from master.dbo.spt_values

    where type ='P'

    and number between 1 and 52

    order by newid()

    select top 5 number

    from master.dbo.spt_values

    where type ='P'

    and number between 1 and 52

    order by newid()

    Far away is close at hand in the images of elsewhere.
    Anon.

  • October 18, 2004 at 10:25 am

    #527065

    I think this will work. I wanted to simulate shuffling and dealing hands.

    I can assign a card to each number like this:

    #1 = 2 of Hearts, #2 = 3 of Hearts and so forth....

     

    Thanks

  • October 19, 2004 at 2:29 am

    #527134

    The point with my example (and David's) was just to show how to shuffle using NEWID()

    Just create your 'deck' table with the cards you need, and then you could probably just order by NEWID() to get a reasonably random hand.

    /Kenneth

  • October 19, 2004 at 8:45 am

    #527194

    Joe,

    I'm pretty sure that none of the Perfect Shuffle algorithms had a DBMS in mind! Do you really believe that a cursor is better than the ORDER BY NEWID() solution? The latter will perform better, take a lot less code to write, and will produce acceptable results. And both solutions use proprietary syntax. So what's the pro-cursor argument?

    --
    Adam Machanic
    whoisactive

  • October 22, 2004 at 8:07 am

    #527658

    Thanks to all that responded! Started building the process using NEWID().

  • October 26, 2004 at 6:40 am

    #527964

    The only question I have is if you need to keep track of the cards that have been dealt. You wouldn't want a dealer playing a Second Ace of Spades in a later hand if the shuffle should not occurr between each play.

    If that is the case then you may want to store the run in another table during play to keep the shuffle in the current order and so you can mark out of play as they pass or even better place in a cursor (yes on purpose) and proceed thru it until not enough cards remain for new play. Then reshuffle at that point.

    Otherwise I support using the NEWID() becuase there is no random function in SQL that will meet the needs. Technically NEWID() thou is not random but it will change the sequence enough to be far superior to RAND() or going out of your way to write a custom piece of code.

  • October 26, 2004 at 9:41 am

    #528005

    Is this a college course question?

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