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Asked: 2026-06-14T12:02:56+00:00

Background: I’m currently developing a simple online quiz. After the user has answered a

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Background: I’m currently developing a simple online quiz. After the user has answered a simple question, the user gets the chance to improve their chances of winning by doing small tasks.

Every lot the user earns is inserted into a separate row, so when I need to find a “random” lot, their chances of winning are increased (please correct me if I’m wrong).

Sample data from the lots table:

LotId      ParticipantId      Created
1          1                  2012-11-16 12:00:00
2          2                  2012-11-16 12:02:00    
3          2                  2012-11-16 12:06:00 
4          2                  2012-11-16 12:15:00    
5          3                  2012-11-16 12:16:00

This means that the participant with ParticipantId 2 has three lots, and therefore a statistically bigger chance of winning compared to the other participants.

What I need to do: When I need to draw a winner, I select a random lot from the lots table. After this I need to find the information on the winner.

Currently I use this following SELECT (any comments on improving the SELECT are appreciated), and then later in my code I have another SELECT with the user’s information.

SELECT TOP 1 LotId, ParticipantId FROM Sample_Lots WITH (NOLOCK)
WHERE
    CAST(Created AS DATE) = '2012-11-16'
    AND
    ParticipantId NOT IN
    (
        SELECT ParticipantId FROM Sample_Winners WITH (NOLOCK)
        WHERE
            ParticipantId IS NOT NULL
            AND
            CAST(ThisDate AS DATE) = '2012-11-16'
    )
    AND
    ParticipantId IN
    (
        SELECT ParticipantId FROM Sample_Participants WITH (NOLOCK)
        WHERE
            ParticipationConfirmed IS NOT NULL
    )
ORDER BY NEWID()

I can’t work my head around this. I need a random lot, and from this random lot I need to get the user’s information in the same SELECT. Any ideas?

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1 Answer

  1. Editorial Team

    Assuming your user information is found in a table named Participants, with columns ParticipantId, FirstName, and LastName, here is an example using a JOIN to that table:

    SELECT TOP 1 sl.LotId, sl.ParticipantId, p.FirstName, p.LastName 
FROM Sample_Lots sl 
INNER JOIN Participants p ON sl.ParticipantId = p.ParticipantId WITH (NOLOCK)
WHERE
    CAST(Created AS DATE) = '2012-11-16'
    AND
    sl.ParticipantId NOT IN
    (
        SELECT ParticipantId FROM Sample_Winners WITH (NOLOCK)
        WHERE
            ParticipantId IS NOT NULL
            AND
            CAST(ThisDate AS DATE) = '2012-11-16'
    )
    AND
    sl.ParticipantId IN
    (
        SELECT ParticipantId FROM Sample_Participants WITH (NOLOCK)
        WHERE
            ParticipationConfirmed IS NOT NULL
    )
ORDER BY NEWID()
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