I saw that this problem was signaled from last year, I put in once more...
The incremental load of SCD2 dimension is producing nesting loops, and for me, it's a showstopper. I cannot use dimensions any more, have to program everything manually.
The reason of nesteed loop is the lookup table which join delta table and dimension and the blind condition for getting the last version to be modified of the dimension table - something like:
OUTGRP1.SMARTCARD_SID (+)= INGRP1.SMARTCARD_SID AND
(OUTGRP1.START_DT IS NULL OR
(OUTGRP1.END_DT IS NULL AND INGRP1.START_DT >= OUTGRP1.START_DT) OR
(OUTGRP1.END_DT IS NOT NULL AND INGRP1.START_DT between OUTGRP1.START_DT and OUTGRP1.END_DT)
This kind of blind conditions can be very easily translated if I have for example an END_DT which is not null (a hipotatical date like 31.12.9999) or by using a flag like LAST_VERSION of the data.
Unfortunately I cannot modiy either this behaviour, by expanding in Deisgner the dimension object I can only see what it generates, never to improve.