What are the features of the NZDT method for heterogeneous system copies? There are 2 correct answers to this question

What are the features of the NZDT method for heterogeneous system copies? There are 2 correct answers to this question
A . It allows restriction.free transports to the source system while triggers are active
B. It logs table data changes based on database triggers
C. It provides a proxy system as central migration controller on the target database system
D. It synchronizes data between the source and the target database system

Answer: B,D