SELECT DISTINCT
users.UserLogin,
users.UserPassword,
ppersons.Surname,
ppersons.Name,
ppersons.Fathername,
ppersons.RoadName,
sum(courses.HourWeight)
FROM
users
INNER JOIN ppersons ON (users.UserLink = ppersons.PPersonID)
INNER JOIN stat_tests ON (users.UserID = stat_tests.UserID)
INNER JOIN courses ON (stat_tests.TestID = courses.CourseID)
WHERE
(stat_tests.StatTestResult >= '0,75')
GROUP BY UserLogin, UserPassword, Surname, Name, Fathername, RoadName