>>>>
>>>>You should have indexes on:
>>>>'koers_hist_tot.dat_krs',
>>>>'fondsen.fonds_cd',
>>>>'koers_hist_tot.fonds_cd'
>>>
>>>But if I index on fondsen it would take some time, so what is the use of this?
>>
>>It's supposed to be done during database design, i.e. index already exists when you run query.
>
>Oh I see, thanks.

You should also look at Naomi suggestion. I don't think that inner join will return exactly the same as outer join in your case, but maybe you really want inner join return? Inner join will run faster.