DROP TRIGGER tri_consume_pk
;

DROP SEQUENCE seq_consume_pk
;

DROP TABLE consume 
;

CREATE TABLE consume (
  consume_id NUMBER,
  consume_type VARCHAR2(10)
)
;

ALTER TABLE consume ADD CONSTRAINT pk_consume PRIMARY KEY (
  consume_id
)
;

CREATE SEQUENCE seq_consume_pk
  START WITH 1 
  INCREMENT BY 1 
  NOMAXVALUE
;

CREATE TRIGGER tri_consume_pk
  BEFORE INSERT ON consume
  FOR EACH ROW
BEGIN
  SELECT seq_consume_pk.NEXTVAL INTO :NEW.consume_id FROM dual;
END
;