Question : Sql Non Disctinct possibility ?

I would like to know if it's possible with an sql query to do thing like non distinct.

i explain, i'd use query like :

select * from my datatable where pk=5 or pk = 8 or pk = 5

Actually i get 2 lines where pk=5 or 8

I'd like if i send pk more than once that i get it more than one in the result of the query. So for the query i'll have 3 Lines and 2 times the line with the pk 5.

Thanks for your help

Alex

Answer : Sql Non Disctinct possibility ?

select * from my datatable where pk=5
union
select * from my datatable where pk=5 or pk = 8 or pk = 5