MySQL 8.0

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CREATE TABLE test (id INT);
CREATE TABLE debug (info TEXT);
CREATE TRIGGER tr
BEFORE INSERT
ON test
FOR EACH ROW
    INSERT INTO debug VALUES (CONCAT('=', NEW.id, '='))
SET @@sql_mode:= '';
INSERT INTO test VALUES (1);
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

id

1

INSERT INTO test VALUES ('2');
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

id

1

2

INSERT INTO test VALUES ('3a');
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

id

1

2

3

INSERT INTO test VALUES ('a4');
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

=0=

id

1

2

3

0

SET @@sql_mode:= 'STRICT_TRANS_TABLES';
INSERT INTO test VALUES (5);
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

=0=

=5=

id

1

2

3

0

5

INSERT INTO test VALUES ('6');
SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

=0=

=5=

=6=

id

1

2

3

0

5

6

INSERT INTO test VALUES ('7a');
Data truncated for column 'id' at row 1

SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

=0=

=5=

=6=

id

1

2

3

0

5

6

INSERT INTO test VALUES ('a8');
Incorrect integer value: 'a8' for column 'id' at row 1

SELECT * FROM debug;
SELECT * FROM test;

info

=1=

=2=

=3=

=0=

=5=

=6=

id

1

2

3

0

5

6