ALTER TABLE contig_accession ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;
ALTER TABLE contig_comment ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;
ALTER TABLE contig_definition ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;
ALTER TABLE contig_names ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;
ALTER TABLE contig_version ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;
ALTER TABLE contig_xrefs ADD FOREIGN KEY (id) REFERENCES contig(id) ON DELETE CASCADE;