Re: *Measuring sql performance (elapsed time and scalability) by number of logical reads

I think you have been a bit short in the problem description.

You just meant that all the requested data is already in buffer and no physical read is needed.
Thanks but we have no information on the nature of the sql, the amount of data, the expected goal.
Bad or good SQL is a ratio of these. What if I read one million blocks from my multi gig db block buffer
to return a tiny rowset for the worse ever seen SQL, it will satisfy your prerequisite and still be very bad. 

Excuse me for not being clear, I meant, theoretically speaking:

SQL 1 reads n1 blocks from buffer (no physical read) to complete, elapsed time t1
SQL 2 reads n2 (where n2 > n1) blocks from buffer (no physical read) to complete, elapsed time t2

t1 is greater than t2

Always theoretically/hypothetical speaking:
could anyone comment the possibile reasons behind such behaviour.



Regards,
Dimitre



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