以不同的列類型科拉姆的最新細節在MySQL

Question

我有多個用戶

examscoreid | examscorenum | examresult | userid | examtype 
55     89    P  7760  1 
54     78    P  7760  3 
53     90    P  7760  5 
52     89    P  7760  4 
41     80    P  7666  2 
44     80    P  7666  2 

我需要用不同的examtype的examscorenum和最新examscoreid與examtype分組

相同的記錄類型的數據表

結果應該是像

examscoreid | examscorenum | examresult |  userid | examtype 
    55     89    P  7760  1 
    54     78    P  7760  3 
    53     90    P  7760  5 
    44     80    P  7666  2 

見的用戶ID 7666得到了兩列同examtype但reequired結果應該包含最新的考試scoreid（採取44不41）

同樣地，我需要整個用戶數據

示例查詢

SELECT examscorenum FROM `exams` WHERE userid in (7760,7666) group by examtype,userid order by examscoreid desc 

我得到的數據，但對於用戶ID 7666我得到examscoreid 41不44

Answer 1

怎樣的結果瞭解以下信息：

create table #exams 
(
    examscoreid int, 
    examscorenum int, 
    examresult varchar(1), 
    userid int, 
    examtype int 
) 

insert into #exams values(55, 89, 'P', 7760, 1) 
insert into #exams values(54, 78, 'P', 7760, 3) 
insert into #exams values(53, 90, 'P', 7760, 5) 
insert into #exams values(52, 89, 'P', 7760, 4) 
insert into #exams values(41, 80, 'P', 7666, 2) 
insert into #exams values(44, 80, 'P', 7666, 2) 

SELECT distinct t1.examscoreid, t1.examscorenum, t1.examresult, t1.userid, t1.examtype 
FROM #exams t1 
JOIN 
(
    select userid, max(examscoreid) as maxscoreid, examtype 
    from #exams 
    group by userid, examtype 
) t2 
    on t1.userid = t2.userid 
WHERE t1.userid in (7760,7666) 
    AND t1.examscoreid = t2.maxscoreid 
order by t1.examscoreid desc 

drop table #exams