text: USE dedc;
  
  BEGIN;
  
  SET foreign_key_checks=0;
  TRUNCATE TABLE entity; 
  TRUNCATE TABLE element; 
  TRUNCATE TABLE link; 
  TRUNCATE TABLE element_list; 
  TRUNCATE TABLE dianode;
  TRUNCATE TABLE dfd_ancestry;
  TRUNCATE TABLE node;
  SET foreign_key_checks=1;
  
  COMMIT;
  