Multiple Many to Many Relationships JOINed in MySQL - mysql

Question

For a project I'm working on, I am trying to query a time clock but when I LEFT JOIN multiple many to many (or in a single users' record sense, 1 to many) it creates duplicate entries, so when it's grouped by, the aggregate totals are incorrect.
Given the below mock schema:
And a query:
SELECT
UserTbl.UserID,
CONCAT_WS(", ", UserTbl.LastName, UserTbl.FirstName) AS UserName,
SUM(TIMESTAMPDIFF(MINUTE, TimeClockTbl.StartDateTime, TimeClockTbl.EndDateTime)) AS ClockedInMinutes,
FROM
Users AS UserTbl
LEFT JOIN
TimeClock AS TimeClockTbl
ON UserTbl.UserID = TimeClockTbl.UserID
LEFT JOIN
UserRoles AS UserRoleTbl
ON UserTbl.UserID = UserRoleTbl.UserID
WHERE
UserRoleTbl.RoleID IN (1,2,3)
GROUP BY
UserTbl.UserID
ORDER BY
UserTbl.LastName ASC,
UserTbl.FirstName ASC;
If the user only has 1 role, assigned, it works fine, but if there is a second or third role assigned, it seems to multiply the final result. I considered using a GROUP_CONCAT for the roles and filtering after, but that doesn't seem to be efficient. I also considered subqueries to calculate the clocked in hours for a given user, but I felt that would have the same result. It's also important to note that this is scaled to have a TimeClock table with multiple entries, and a Scheduled table with multiple entries as well.
How can I do this with a decent amount of efficiency?

Answer 1

Simple decision:
SELECT UserTbl.UserID,
CONCAT_WS(", ", UserTbl.LastName, UserTbl.FirstName) AS UserName,
SUM(TIMESTAMPDIFF(MINUTE, TimeClockTbl.StartDateTime, TimeClockTbl.EndDateTime)) AS ClockedInMinutes,
FROM Users AS UserTbl
LEFT JOIN TimeClock AS TimeClockTbl ON UserTbl.UserID = TimeClockTbl.UserID
WHERE UserTbl.UserID IN( SELECT UserID FROM UserRoles WHERE RoleID IN (1,2,3) )
GROUP BY UserTbl.UserID
ORDER BY UserTbl.LastName ASC, UserTbl.FirstName ASC;
Concept for similar situations - consistent join:
SELECT A.*,
SUM(TIMESTAMPDIFF(MINUTE, TimeClockTbl.StartDateTime, TimeClockTbl.EndDateTime)) AS ClockedInMinutes,
MAX(A.RolesTitle) AS RolesTitle
FROM (
SELECT UserTbl.UserID,
CONCAT_WS(", ", UserTbl.LastName, UserTbl.FirstName) AS UserName,
FirstName, LastName,
GROUP_CONCAT(Roles.Title) as RolesTitle
FROM Users AS UserTbl
JOIN UserRoles AS UserRoleTbl ON UserTbl.UserID = UserRoleTbl.UserID
JOIN Roles ON Roles.RoleID=UserRoleTbl.RoleID
WHERE UserRoleTbl.RoleID IN (1,2,3)
GROUP BY UserTbl.UserID
) A
LEFT JOIN TimeClock AS TimeClockTbl ON A.UserID = TimeClockTbl.UserID
GROUP BY A.UserID
ORDER BY A.LastName ASC, A.FirstName ASC;