Ignoring Errors
---------------

Normally INSERT stops and rolls back when it encounters an error.

By using the IGNORE keyword all errors are converted to warnings, which will
not stop inserts of additional rows.

The IGNORE and DELAYED options are ignored when you use ON DUPLICATE KEY
UPDATE.

Prior to MySQL and MariaDB 5.5.28, no warnings were issued for duplicate key
errors when using IGNORE. You can get the old behavior if you set OLD_MODE to
NO_DUP_KEY_WARNINGS_WITH_IGNORE.

Examples
--------

CREATE TABLE t1 (x INT UNIQUE);

INSERT INTO t1 VALUES(1),(2);

INSERT INTO t1 VALUES(2),(3);
ERROR 1062 (23000): Duplicate entry '2' for key 'x'
SELECT * FROM t1;
+------+
| x    |
+------+
|    1 |
|    2 |
+------+
2 rows in set (0.00 sec)

INSERT IGNORE INTO t1 VALUES(2),(3);
Query OK, 1 row affected, 1 warning (0.04 sec)

SHOW WARNINGS;
+---------+------+---------------------------------+
| Level   | Code | Message                         |
+---------+------+---------------------------------+
| Warning | 1062 | Duplicate entry '2' for key 'x' |
+---------+------+---------------------------------+

SELECT * FROM t1;
+------+
| x    |
+------+
|    1 |
|    2 |
|    3 |
+------+

See INSERT ON DUPLICATE KEY UPDATE for further examples using that syntax.

URL: https://mariadb.com/kb/en/insert-ignore/