>>>
>>>1) With this query you only will get records with dat_krs from koers_hist_tot = dat_e_bkp, so there is no need to use left join, it is essentially inner join anyway.
>>>
>>>2) You may first get koers_hist_tot.dat_krs, koers_hist_tot.fond_cd from Koers_Hist_tot and then use a second select to get records from the big table, e.g. in VFP9 you may do
>>>
>>>select fondsen.*, InnerSel.dat_krs from Fondsen inner join (select koers_hist_tot.dat_krs, koers_hist_tot.fond_cd where ...) InnerSel on
>>>FondSen... = InnerSel..
>>>
>>>In VFP5 you can use two selects.
>>
>>I'll try both out and see if this helps me. Thanks.
>
>Without the index on the field engaged in the join condition you probably would not get speed increase.

Your message was very insightful for me, espescially how an left outer join works. I didn't know that the where clause was destroying this, after all I just needed an inner join which runs very fast now.