Converting column containing string value '0' to enum converts to empty string

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Your MariaDB connection id is 1624425

Server version: 10.11.6-MariaDB-1:10.11.6+maria~ubu2004-log mariadb.org binary distribution

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MariaDB [(none)]> create database phils_test;

Query OK, 1 row affected (0.004 sec)

MariaDB [(none)]> use phils_test

Database changed

MariaDB [phils_test]> create table enum_test2(c1 varchar(20));

Query OK, 0 rows affected (0.007 sec)

MariaDB [phils_test]> insert into enum_test2 values ('first'),('second'),('third'), (null), ('0');

Query OK, 5 rows affected (0.003 sec)

Records: 5  Duplicates: 0  Warnings: 0

MariaDB [phils_test]> select * from enum_test2;

+--------+

| c1     |

+--------+

| first  |

| second |

| third  |

| NULL   |

| 0      |

+--------+

5 rows in set (0.001 sec)

MariaDB [phils_test]> alter table enum_test2 modify c1 enum('first','third', 'second');

Query OK, 5 rows affected (0.012 sec)

Records: 5  Duplicates: 0  Warnings: 0

MariaDB [phils_test]> select * from enum_test2;

+--------+

| c1     |

+--------+

| first  |

| second |

| third  |

| NULL   |

|        |

+--------+

5 rows in set (0.001 sec)

MariaDB [phils_test]> drop database phils_test;

Query OK, 1 row affected (0.024 sec)