CREATE TABLE Games (EntryFee INT, Rake INT, TotalEntry INT);
CREATE TABLE Transaction1 (UserID VARCHAR(25));

INSERT INTO Games VALUES 
    (30,16,150),(45,20,100),(15,5,50),(25,20,300),(10,8,270);

INSERT INTO Transaction1 VALUES ('Daniel'),('David'),('John'),('Martha');

SELECT Games.EntryFee, Games.Rake, Games.TotalEntry, COUNT(distinct Transaction1.UserID) AS CountUser,
(Games.EntryFee * Games.Rake / (100 + Games.Rake) * Games.TotalEntry / COUNT(distinct Transaction1.UserID))
AS Calculate
FROM Games JOIN Transaction1 GROUP BY Games.EntryFee, Games.Rake, Games.TotalEntry;

结果：

+==========+======+============+===========+==============+
| EntryFee | Rake | TotalEntry | CountUser | Calculate    |
+==========+======+============+===========+==============+
| 10       | 8    | 270        | 4         | 50.00000000  |
+----------+------+------------+-----------+--------------+
| 15       | 5    | 50         | 4         | 8.92857500   |
+----------+------+------------+-----------+--------------+
| 25       | 20   | 300        | 4         | 312.50000000 |
+----------+------+------------+-----------+--------------+
| 30       | 16   | 150        | 4         | 155.17242500 |
+----------+------+------------+-----------+--------------+
| 45       | 20   | 100        | 4         | 187.50000000 |
+----------+------+------------+-----------+--------------+

示例查询

SELECT (
    SELECT sum(EntryFee * Rake/(100 + Rake)*TotalEntry) FROM Games
)/(
    SELECT count(distinct UserID) FROM Transaction
) MyResult