error...what to do?

The I am trying to do a set difference query. The query question is as
follows: 3.Find the names and costs of all abilities that Zidane can
learn,

but that Steiner cannot. Can anyone help with this ..please.

The tables to use are as follows:

beckerbalab2=> select * from ffix_ability;

ability_name | ability_description |
type | cost

----------------------+------------------------------------------------+
------------+------

Flee | Escape from battle with high probability. |
Active | 0

Cure | Restores HP of single/multiple. |
Active | 6

Power Break | Reduces the enemy's attack power. |
Active | 8

Thunder Slash | Causes Thunder damage to the enemy. |
Active | 24

Auto-Haste | Automatically casts Haste in battle. |
Passive | 9

Counter | Counterattacks when physically attacked. |
Passive | 8

MP+20% | Increases MP by 20% |
Passive | 8

Thievery | Deals physical damage to the target |
Active | 8

Fire | Causes Fire damage to single/multiple targets. |
Active | 6

Flare | Causes Non-Elemental damage. |
Active | 40

Leviathan | Causes water damage to all enemies. |
Active | 42

beckerbalab2=> select * from ffix_can_wear;

character_name | equipment_name

----------------+----------------------

Dagger | Rod

Dagger | Aquamarine

Zidane | Aquamarine

Vivi | Aquamarine

Steiner | Diamond Sword

Steiner | Ragnarok

Dagger | Running Shoes

Zidane | Running Shoes

Vivi | Running Shoes

Steiner | Running Shoes

Dagger | Ritual Hat

Zidane | Ritual Hat

Vivi | Ritual Hat

Dagger | Angel Earrings

Zidane | Dagger

Zidane | The Tower

Dagger | Leather Hat

Zidane | Leather Hat

Vivi | Leather Hat

Vivi | Black Robe

Steiner | Aquamarine

(21 rows)

beckerbalab2=> SELECT ffix_ability.name, ffix_ability.cost

beckerbalab2-> FROM ffix_can_learn NATURAL JOIN ffix_ability

beckerbalab2-> WHERE ffix_can_learn.character_name = 'Zidane'

beckerbalab2-> EXCEPT --this is the difference operator hope it works

beckerbalab2-> SELECT ffix_ability.name, ffix_ability.cost

beckerbalab2-> FROM ffix_can_learn NATURAL JOIN ffix_ability

beckerbalab2-> WHERE ffix_can_learn.character_name = 'Steiner';

ERROR: No such attribute or function 'name'

beckerbalab2=>