Yes, but it is my understanding of SQL that a query on a non-indexed column 
will create a temporary index in mySQL and maybe others. I might be wrong about 
that. But Foxpro does not do that. In fact if you set a filter or seek using a 
FOR statement that has no indexed columns or has some non-indexed columns, 
Foxpro will proceed at a reduced speed without any temporary indexing. 
Of course, you could index all columns that you will ever search on, but this 
is not always the best, because depending on the application, many columns may 
only occasionally be searched, and the overhead of updating all those indexes 
becomes counter-productive in terms of speed overall. So the principle of 
indexing columns that you search often, as you stated is the real life standard 
for indexing imho. 

Bob


On May 31, 2012, at 11:19 AM, Ruslan Zasukhin wrote:

> On 5/31/12 8:14 PM, "Bob Sneidar" <b...@twft.com> wrote:
> 
>> Foxpro does, but it's slow.
> 
> You mean that foxpro can do
>    search on column that is not indexed ?
> 
> Well, of course each db engine can do this.  :-)
> And Valentina, and Light, and mySQL, ...
> And yes it is much slower than indexed search,


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