Which of the following statements are correct?

DataWorks can be used to develop and configure data sync tasks.

Which of the following statements are correct? (Number of correct answers: 3) Score 2
A . The data source configuration in the project management is required to add data source
B . Some of the columns in source tables can be extracted to create a mapping relationship between fields, and constants or variables can’t be added
C . For the extraction of source data, "where" filtering clause can be referenced as the criteria of incremental synchronization
D . Clean-up rules can be set to clear or preserve existing data before data write

Answer: A,B,D