MySQL 8.0

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CREATE TABLE t1 (id1 INT AUTO_INCREMENT PRIMARY KEY) AUTO_INCREMENT = 10;
CREATE TABLE t2 (id2 INT AUTO_INCREMENT PRIMARY KEY, id1 INT) AUTO_INCREMENT = 20;
CREATE TABLE t3 (id3 INT AUTO_INCREMENT PRIMARY KEY) AUTO_INCREMENT = 30;
CREATE TRIGGER tr 
AFTER INSERT ON t3
FOR EACH ROW
BEGIN
  INSERT INTO t1 VALUES (DEFAULT);
  INSERT INTO t2 VALUES (DEFAULT, LAST_INSERT_ID());
END
INSERT INTO t3 VALUES (DEFAULT), (DEFAULT);

Records: 2  Duplicates: 0  Warnings: 0

SELECT * FROM t3;
SELECT * FROM t1;
SELECT * FROM t2;

id3

30

31

id1

10

11

id2
id1

20
10

21
11