Warning about returning is not supported when using MariaDB

[siakc]

Documentation notes 'If you want to use a MariaDB instance, you can use the mysql driver.'
So we are using client: 'mysql' to initialize the client.
When the app starts and executes a query containing RETURNING clause, we see '.returning() is not supported by mysql and will not have any effect.' in the log.
It also seems that in this case returning is effectively ignored.
As knex claims that it supports MariaDB. This should not be the case as MariaDB supports returning.

Knex version: Latest
Database + version: MariaDB any
OS: any

[siakc]

Further investigation showed that it is actually working in mariadb contradicting my initial assessment. The only problem is the incorrect warning.

[siakc]

The reason is Mariadb like Mysql returns the auto increment primary key field. So returning IS being ignored.