Hi, 
I had the same error, my nodes table look like this: 

MariaDB [ironic]> describe nodes;                                                                                                                                                                                  
+------------------------+--------------+------+-----+---------+----------------+
| Field                  | Type         | Null | Key | Default | Extra          |
+------------------------+--------------+------+-----+---------+----------------+
| created_at             | datetime     | YES  |     | NULL    |                |
| updated_at             | datetime     | YES  |     | NULL    |                |
| id                     | int(11)      | NO   | PRI | NULL    | auto_increment |
| uuid                   | varchar(36)  | YES  | UNI | NULL    |                |
| instance_uuid          | varchar(36)  | YES  | UNI | NULL    |                |
| name                   | varchar(255) | YES  | UNI | NULL    |                |
| chassis_id             | int(11)      | YES  | MUL | NULL    |                |
| power_state            | varchar(15)  | YES  |     | NULL    |                |
| target_power_state     | varchar(15)  | YES  |     | NULL    |                |
| provision_state        | varchar(15)  | YES  |     | NULL    |                |
| target_provision_state | varchar(15)  | YES  |     | NULL    |                |
| provision_updated_at   | datetime     | YES  |     | NULL    |                |
| last_error             | text         | YES  |     | NULL    |                |
| instance_info          | text         | YES  |     | NULL    |                |
| properties             | text         | YES  |     | NULL    |                |
| driver                 | varchar(255) | YES  |     | NULL    |                |
| driver_info            | text         | YES  |     | NULL    |                |
| driver_internal_info   | text         | YES  |     | NULL    |                |
| clean_step             | text         | YES  |     | NULL    |                |
| resource_class         | varchar(80)  | YES  |     | NULL    |                |
| raid_config            | text         | YES  |     | NULL    |                |
| target_raid_config     | text         | YES  |     | NULL    |                |
| reservation            | varchar(255) | YES  |     | NULL    |                |
| conductor_affinity     | int(11)      | YES  | MUL | NULL    |                |
| maintenance            | tinyint(1)   | YES  |     | NULL    |                |
| maintenance_reason     | text         | YES  |     | NULL    |                |
| console_enabled        | tinyint(1)   | YES  |     | NULL    |                |
| inspection_finished_at | datetime     | YES  |     | NULL    |                |
| inspection_started_at  | datetime     | YES  |     | NULL    |                |
| extra                  | text         | YES  |     | NULL    |                |
| boot_interface         | varchar(255) | YES  |     | NULL    |                |
| console_interface      | varchar(255) | YES  |     | NULL    |                |
| deploy_interface       | varchar(255) | YES  |     | NULL    |                |
| inspect_interface      | varchar(255) | YES  |     | NULL    |                |
| management_interface   | varchar(255) | YES  |     | NULL    |                |
| network_interface      | varchar(255) | YES  |     | NULL    |                |
| raid_interface         | varchar(255) | YES  |     | NULL    |                |
| storage_interface      | varchar(255) | YES  |     | NULL    |                |
| power_interface        | varchar(255) | YES  |     | NULL    |                |
| vendor_interface       | varchar(255) | YES  |     | NULL    |                |
+------------------------+--------------+------+-----+---------+----------------+
40 rows in set (0.01 sec)