check if a column contains ALL the values of another column - Mysql

Question

Let\'s suppose I have a table T1 with people IDs and other stuff IDs, as the following

Table: T1
personID | stuffID 
    1    |    1
    1    |    2
    1            


        

Answer 1

select personID from T1 group by personID having count(distinct stuffID) in (select count(distinct stuffID) from T2)

select count(distinct stuffID) from T2 <-- Would give the total number of distinct countIDs

group by personID having count(distinct stuffID) <-- after grouping by personId , counting the number of stuffIds that personId has.

So both the counts should be equal to get the desired result.