@Entity
@Table(name = "route")
public class Route implements Serializable {
     .....................
     ....................
     @OneToMany(fetch = FetchType.LAZY, mappedBy = "route",  cascade = CascadeType.REMOVE)
     private List<ExcFlow> flowList;
}

@Entity
@Table(name = "exc_flow")
public class ExcFlow implements Serializable {
         ......................................
         ......................................
    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "route_path_fk")
    private RoutePath route;
}

CREATE TABLE exc_flow
(
  exc_flow_id bigserial NOT NULL,
  create_date timestamp without time zone NOT NULL,
  ..................................
  route_path_fk bigint,
  CONSTRAINT cfid_exc_flow_pkey PRIMARY KEY (exc_flow_id),
  CONSTRAINT fk4773145eefa0a0f5 FOREIGN KEY (route_path_fk)
      REFERENCES cfid_route_path (route_path_id) MATCH SIMPLE
      ON UPDATE NO ACTION ON DELETE NO ACTION
)

CREATE TABLE route_path ---- сущность Route 
(
  route_path_id bigint NOT NULL,
  create_date timestamp without time zone NOT NULL,
  expires_date timestamp without time zone NOT NULL,
  last_modif_date timestamp without time zone NOT NULL,
  opt_status_flag character varying(255) NOT NULL,
  route_name character varying(255) NOT NULL,
  route_path_label character varying(255) NOT NULL,
  CONSTRAINT cfid_route_path_pkey PRIMARY KEY (route_path_id),
  CONSTRAINT cfid_route_path_route_name_key UNIQUE (route_name)
)


CREATE TABLE exc_flow
(
  exc_flow_id bigserial NOT NULL,
  create_date timestamp without time zone NOT NULL,
  destination character varying(255),
  expires_date timestamp without time zone NOT NULL,
  last_modif_date timestamp without time zone NOT NULL,
  ops_status_flag character varying(255) NOT NULL,
  ors_application character varying(255) NOT NULL,
  source character varying(255) NOT NULL,
  route_path_fk bigint,
  CONSTRAINT exc_flow_pkey PRIMARY KEY (exc_flow_id),
  CONSTRAINT fk4773145eefa0a0f5 FOREIGN KEY (route_path_fk)
      REFERENCES cfid_route_path (route_path_id) MATCH SIMPLE
      ON UPDATE NO ACTION ON DELETE NO ACTION
)

REFERENCES cfid_route_path (route_path_id)