>><snip>
>>
>>Hi Fabio. Any idea why there would be this difference in speed between these methods?
>>
>>Ciao!
>
>Of course, only hypothesis:
>- LOCATE it demands of the additional operations
>because VFP have to store the expression and status
>for execute a eventual successive CONTINUE operation;
>- SCAN it does not have to make this job additional;
>honestly this explanation me seems insufficient to explain all,
> SCAN has an overload which had to the control of endscan.
>
>- LOOKUP it is the true force of VFP, the inner code of search,
>it is effectively 2x faster than LOCATE;
>an explanation part is in the fact that LOCATE/SCAN must revalue
>all the expression for every record, LOOKUP use a C data driver code (?)
>( get the parm2 and compare with the field=parm3 )
>
>An other small improvement can be obtained adding NOOPTIMIZE
>(if it is sure that VFP cannot optimize the FOR),
>in this case VFP jumps all the phase of analysis for the optimization.
>If it is present WHILE, NOOPTIMIZE it is not required,
>because with WHILE VFP it cannot optimize the FOR.
>
>Ciao
>
>Fabio

Hi Fabio - thanks for the info. Most interesting and something to experiment with.

Thanks and ciao!