[NOV - 6] - Initial to support BREAKPOINT
- New class FD
- New variable executeflag to decide whether or not to EXECUTE the SQL, but sql will be generated and saved.
- New notation in XML to indicate FD
- Add FD to CompareData.java
- Add a breakpoint while do parallel comparison, if value in the column is greater than threshold in FD, it will not update executeflag (keep it to 1, otherwise 0)