thanks!
haha,

when debugger is off,
and change:
Debug b
Debug ElapsedMilliseconds()-q
to:
q=ElapsedMilliseconds()-q
MessageRequester("",""+b+~"\n"+q)
use virtual tables out:
b;my pc =-5
ElapsedMilliseconds()-q;my pc =342
use Select out:
b;my pc =-155
ElapsedMilliseconds()-q;my pc =174
@GedB:
thanks!

You are like a teacher to guide students to progress, thank you again for your link !