Question

I have a small MS Access database containing four tables and are struggeling with a MAX(Date) query which involves all tables. Any help will be greatly appreciated.

Overview of the database:

TABLE          COLUMNS

Person         Person_ID |....
Games          Game_ID | Name |....
Played_Games   Played_Games_ID | Game_ID | Date |....
Participation  Played_Games_ID | Person_ID |...

To list out all games and what date each of them were last played by any person I use:

SELECT DISTINCT Games.Name,
(SELECT MAX(Date) FROM Played_Games WHERE Played_Games.Game_ID = Games.Game_ID) AS Date_Last_Played
FROM Games
ORDER BY Games.Name

This works great, but I would also like to list what date each of them were last played by members of a certain group of persons. Any help with that will be greatly appreciated.

I asked a somewhat similar question some days ago, but then my goal was to list out all games, how many times each game is played in total and how many times each games is played by members of a certain group of persons (Persons 1 and 2 are just an example). GarethD helped me out with that one just perfect by the code below. I’ve tried to alter this code to solve my new task, cause I guess much of this logic/structure can be reused, but so far I’ve not been successful on my own 🙁

SELECT  Games.Name,
        IIF(ISNULL(TimesPlayed),0,TimesPlayed) AS Times_Played,
        IIF(ISNULL(TimesPlayedByGroupMembers),0,TimesPlayedByGroupMembers) AS Times_Played_By_Group_Members
FROM    Games
        LEFT JOIN
        (   SELECT  Game_ID,
                    COUNT(*) AS TimesPlayed,
                    SUM(IIF(ISNULL(Participation.Played_Games_ID),0,1)) AS TimesPlayedByGroupMembers
            FROM    Played_Games
                    LEFT JOIN
                    (   SELECT  Played_games_ID
                        FROM    Participation
                        WHERE   Person_ID IN (1, 2)
                        GROUP BY Played_games_ID
                    ) AS Participation
                     ON Participation.Played_Games_ID = Played_Games.Played_Games_ID
            GROUP BY Game_ID
        ) AS Played_Games
            ON Played_Games.Game_ID = Games.Game_ID
ORDER BY Games.Name

Any help will be greatly appreciated. Thanks for your time!

Answer 1

I’ve just added in a couple of lines to the last answer I posted to show the date last played, and the date last played by group members, next to the number of times played. Hope this is what you are after.

SELECT  Games.Name,
        IIF(ISNULL(TimesPlayed),0,TimesPlayed) AS Times_Played,
        IIF(ISNULL(TimesPlayedByGroupMembers),0,TimesPlayedByGroupMembers) AS Times_Played_By_Group_Members,
        LastPlayed,
        LastPlayedByGroupMembers
FROM    Games
        LEFT JOIN
        (   SELECT  Game_ID,
                    COUNT(*) AS TimesPlayed,
                    SUM(IIF(ISNULL(Participation.Played_Games_ID),0,1)) AS TimesPlayedByGroupMembers,
                    MAX(Played_Games.[Date]) AS LastPlayed,
                    MAX(IIF(ISNULL(Participation.Played_Games_ID),NULL,Played_Games.[Date])) AS LastPlayedByGroupMembers
            FROM    Played_Games
                    LEFT JOIN
                    (   SELECT  Played_games_ID
                        FROM    Participation
                        WHERE   Person_ID IN (1, 2)
                        GROUP BY Played_games_ID
                    ) AS Participation
                     ON Participation.Played_Games_ID = Played_Games.Played_Games_ID
            GROUP BY Game_ID
        ) AS Played_Games
            ON Played_Games.Game_ID = Games.Game_ID
ORDER BY Games.Name