Hi,
I was just stating my findings, it would appear that the "==" is evaluated on each iteration, whereas the SET EXACT & SET ANSI are not.

Do some tests yourself, create a dbf with 15mil + records and a number of keys, create several keys based on integer, character & binary fields and see what your findings are. Conservatively it gives a 10% difference in timings, remember to reboot the workstation between tests to get reliable results.

>>Hi,
>>I have recently done some performance testing on large datasets in VFP9, as result we are now using SET EXACT ON & SET ANSI ON and not using "==" as it does have a perceivable impact on performance when processing large amounts of data.
>
>When a scientist wants to make such a claim in a journal they must provide evidence and practices which others can duplicate. Are we not doing computer science? IOW would you please prove that?
>
>>
>>>Good Friday Morning to All,
>>>
>>>I ran into a problem using <> operator where the following happens:
>>>

>>>cTest1 = "This is a sample string"
>>>cTest2 = "This is a sample string test"
>>>? cTest2 <> cTest1  && returns .F.
>>>

>>>
>>>Now I am thinking if I should do away with using <> operator because it always relies on SET EXACT ON and just use "==" in ALL my comparisons. What do you think?
>>>
>>>Thank you.