Jim,
Thanks much!
Pity though that FP / VFP doesn't internally "optimize" GO TOP or GO BOTTOM. Could only help.
Cheers,
Jim N
>>Jim,
>>
>>I wonder if you could offer a little more reasoning for this one than simply 'locate is optimizeable while GO TOP / GO BOTTOM are not'??
>>
>>The reason should be obvious - ZERO optimization required for the two special cases GO TOP and GO BOTTOM, whereas LOCATE would seem to NEED optimization EVERY time.
>>
>>Just because GO TOP and GO BOTTOM are not optimizeable should *not* immediately lead to the conclusion that they are *not* "optimized" within VFP. And even if not specifically "optimized", their very destinations should lead to an immedaite answer which is the final answer, and not some intermediate answer.
>>
>>Regards,
>>Jim N
>
>Jim,
>
>Ok here's where the difference really show up;
>
> USE MyTable && Has 3,000,000 records sequentially IDed in TabID
> SET FILTER TO TabId > 2,500,000
> GO TOP && Starst a record 1 and cehcks every record until it finds one with an ID > 2,500,000 Hits 2.5 Million records
> LOCATE && Rushmore checks the index and immediately jumps to record 2,500,001 One record hit
>
>The reason that I always use LOCATE rather than GO TOP is that in teh code I am writing I don't always know if there has been a filter set somewhere else.
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