Hai..,
This is Kiran.
In SCD's type we r using change capture and transfernar 
stage.
date fields are using in target level as Eff_start_date and 
Eff_end_date.

Eff_start_date=current date
Eff_end_date  =Currentdate-1.

If any mail me

Regards
Kiran
9393363309

Hai this is praveen kumar yenduri,

from my knowledge.....
in SlowlyChangingDimension ---type 2

we use the stages are Chance Capture Stage,Transformer
Stage,Join Stage and we have to generate once sequence
generator and one stored procedure......

As kiran said he explains only the half of the topic..

the concept is....

the SCD-type2 means...when ever the record is
inserted,updated,deleted...the target table had to be get
updated everytime....that the thing for this case...
we have to use the change capture stage..when using change
capture stage it takes 2 inputs..one is target RDBMS,second
one is Recent RDBMS,as defining the target one as "before"
link and source..ie.,recent as "after"...from that we can
have some change codes ...basing on that codes we can
perform the operations...after getting the change codes...it
had to send to transformer stage their basing upon the codes
the stored procedures had to taken...thats the topic
goes...once you get the idea you can do it....