problem with LEFT JOIN function

[SixK]

Hello,

Can any of you explain me why, when i do this request :

select count(*)
from OBJET as t1 left join COLLECTION as t2
ON t1.numColl = t2.numColl
where t2.numSupp = 0;

I've got an error saying :  Field numObj not found
note that numObj is the Key of table OBJET...

Thank's

-- 
Best regards,
 SixK                          mailto:SixK@stripped