>You can use two betweens with an or seperating them.
>between(tBegin,tUserStart,tUserEnd) OR between(tEnd,tUserStart,tUserEnd)

Yes, except for the case when tBegin is before tUserStart and tEnd is after tUserEnd. I forgot to include this in my graphic example.

01110000000000 <- record excluded
00000000001111 <- record excluded
00111111111000 <- record included

Thanks,