How to reference two table when lack reference column.

Question:How to reference two table when lack reference column.

Example:

1.Create two tables the one of  lack reference column.

CREATE TABLE t1(
t_id NUMBER,
t_age NUMBER
);
INSERT INTO t1 VALUES(1,24);
COMMIT;

CREATE TABLE t2(
t_name VARCHAR2(20)
);
INSERT INTO t2 VALUES('sbn');
COMMIT;

 2.add a column become a reference conditon.

ALTER TABLE t2 ADD t_id NUMBER;
INSERT INTO t2 (t_id) VALUES(1);
SELECT * FROM t2;

SELECT a.t_id,a.t_age,b.t_name
FROM t1 a,t2 b
WHERE a.t_id=b.t_id;