>>

>>SELECT Id, Forename, Compname, SUM(OrdTotal) TotOrd ;
>>FROM clients LEFT JOIN Prsndetl ON Clients.Id = PrsnDetl.ClientId;
>>LEFT JOIN Orders ON Clients.Id = Orders.ClientId;
>>GROUP BY Clients.Id, Clients.Compname, PrsnDetl.Forename;
>>HAVING '01' $ LOWER(Clients.CompName) ;
>>OR 'hr' $ LOWER(PrsnDetl.Forename) ;
>>OR TotOrd = 300
>>

>
>Nice and simple. Do you think it's better than derived table? What is the difference in speed of execution?

It is faster because VFP
execute an on place filtering, respect to a filtering copy as derived table.

But remember that VFP don't optimize HAVING.
In this case it doesn't care because the OR Logic remove every optimizable way