Oracle 21c

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CREATE TABLE FURNITURE
       (ROOM VARCHAR2(50) CONSTRAINT PK_DEPT PRIMARY KEY,
        APPLIANCE VARCHAR2(50));
BEGIN
INSERT INTO FURNITURE VALUES
        ('BEDROOM','BED');
INSERT INTO FURNITURE VALUES
        ('LIVING ROOM', 'SOFA');
INSERT INTO FURNITURE VALUES
        ('TV ROOM', 'TV');
INSERT INTO FURNITURE VALUES
        ('ALL', 'LAMP');
END;
/
1 rows affected

SELECT r.room,
       f.appliance
FROM   (SELECT room FROM furniture WHERE room <> 'ALL') r
       INNER JOIN furniture f
       ON (r.room = f.room OR f.room = 'ALL')


ROOM
APPLIANCE


BEDROOM
LAMP

LIVING ROOM
LAMP

TV ROOM
LAMP

BEDROOM
BED

LIVING ROOM
SOFA

TV ROOM
TV

ROOM	APPLIANCE
BEDROOM	LAMP
LIVING ROOM	LAMP
TV ROOM	LAMP
BEDROOM	BED
LIVING ROOM	SOFA
TV ROOM	TV