sql - MySQL; Return most frequent occurrence(s) where there may be more than one -

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i have table student ids (sid) , classes (ccode) they're taking.

i'm trying retrieve student ids of student(s) taking highest number of classes, query needs allow fact there might tie.

i know highest number of occurrences of same sid indicate the 1 i'm looking if looking retrieve top record i'd go

mysql> select sid, count(sid) numberofclasses -> student_classes -> group sid -> order numberofclasses desc -> limit 1; +------+-----------------+ | sid  | numberofclasses | +------+-----------------+ | 2040 |               3 | +------+-----------------+

i've tried

mysql> select sid, count(sid) numberofclasses -> student_classes -> group sid -> having numofclasses=3; +------+-----------------+ | sid  | numberofclasses | +------+-----------------+ | 2040 |               3 | | 3040 |               3 | +------+-----------------+

which works because know value of highest number of projects working on 3, need way of putting max() function after = calculate highest value in numberofprojects column of newly created table….

any thoughts?

this original student_classes table…

mysql> select * student_classes; +------+-------+ | sid  | ccode |  +------+-------+ | 2040 | c101  | | 2040 | c102  |          | 2040 | c103  |  | 3282 | c101  |  | 3282 | c102  |  | 2113 | c105  |  | 3040 | c102  |  | 3040 | c105  |  | 3040 | c108  |  +------+-------+

have tried combining 2 approaches using subquery?

select sid, count(sid) numberofclasses student_classes group sid having count(sid) = (select count(sid) n student_classes group sid order n desc limit 1)

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