CREATE TABLE "informix".loy_standard(
    id INT
  , txt VARCHAR( 10 )
) LOCK MODE ROW;

ALTER TABLE "informix".loy_standard
  ADD CONSTRAINT 
    PRIMARY KEY (id)
  CONSTRAINT "informix".pk_loy_standard;

CREATE RAW TABLE "informix".loy_raw(id INT, txt VARCHAR( 10 )) LOCK MODE ROW;

CREATE UNIQUE INDEX "informix".idx_loy_raw_id 
  ON "informix".loy_raw(id);

ALTER TABLE "informix".loy_raw
  ADD CONSTRAINT 
    PRIMARY KEY (id)
  CONSTRAINT "informix".pk_loy_raw;
-- получаем -19831
-- Indexes and referential constraints are not allowed on tables of type raw.

ALTER TABLE "informix".loy_raw
  ADD CONSTRAINT 
    FOREIGN KEY (id) 
      REFERENCES loy_standard
  CONSTRAINT "informix".fk_loy_raw_loy_standard;
-- получаем -19831
-- Indexes and referential constraints are not allowed on tables of type raw.

ALTER TABLE "informix".loy_standard
  ADD CONSTRAINT 
    FOREIGN KEY (id) 
      REFERENCES loy_raw
    CONSTRAINT "informix".fk_loy_standard_loy_raw;
-- получаем -297
-- Cannot find unique constraint or primary key on referenced table <informix.loy_raw>


-- чистим БД от экспериментов
DROP TABLE loy_raw;
DROP TABLE loy_standard;