The SQL error plugin prints (null) as database if the mariadb client is not using any database to execute the SQL.

MariaDB [(none)]> drop database db;

ERROR 1008 (HY000): Can't drop database 'db'; database doesn't exist

MariaDB [(none)]> 

$ cat data/sql_errors.log 

5 (null) 2023-11-29  5:53:31 root[root] @ localhost [] ERROR 1008: Can't drop database 'db'; database doesn't exist : drop database db 

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