Hi Ed,

Of course a whole lot (even beyond the effects of a INDEX on Deleted() can affect performance. For instance, I have a strong belief that fragmented tables are probably better overall than contiguous tables. But since we cannot even "see" the fragmentation we cannot reliably do benchmarking to test this.

But to *me* the evidence is clear that such an index, except in SPECIAL CIRCUMSTANCES, does not much good and can be very detrimantal to performance when SET DELETED ON is employed.

What I still am very uncomfortable about is my feeling that this is a CHANGE from previous versions (though I cannot guess which version it happened on) yet most others conclude that it has *probably* always been this way! Too many experts published the advantage of an INDEX on deleted(), starting about FPD 2.5 or thereabouts and far far far too many people reported dramatic improvement by creating such an index in the past for me to accept that it has always been that way.

Cheers,

Jim N

>Deleted tag can hurt the performance or not. It depends on the way the application (esp. data access) designed. Basically, it may hurt non-discrete usage of SQL-strings, especially as row/record sources.
>
>>Dan,
>>
>>That key on Deleted() is no longer a good idea at all. It will almost surely HURT performance of a VFP application!
>>
>>Some say that it has always been this way, suggesting that we were all misinformed when this "tip" originally made the rounds. I happen to disagree with that opinion, but have no way to prove it one way or the other. Just to be clear, I have NO DOUBT that an INDEX on Deleted() will most likely HURT an app.; I doubt that it has always been this way.
>>
>>Cheers,
>>
>>Jim N
>>
>>
>>
>>>Make sure the program is installed and running from the local machines.
>>>Make sure you're useing buffering. Make sure you're views are optimized sys(3054). Make sure you have a key on Deleted() on all your tables.
>>>
>>>You can also use coverage logging in the Debugger or just step through the program yourself to see which lines are so slow.
>>>
>>>HTH