ERROR: bogus varno: 2

Good night friends
This is my first message, thank you in advance.
I have some databases that I migrated from postgresql 9.5 to 10, and in 
some tables when trying to view SQL I get the following error: "ERROR: 
bogus varno: 2"
After some queries I came to the conclusion that the error appears when 
I have in the table a trigger that has AFTER UPDATE condition.
Example:
"AFTER UPDATE OF notan1 ON public.nota FOR EACH ROW WHEN ((old.notan1 IS 
DISTINCT FROM new.notan1))"

I already ran backup of the database, and I removed the trigger, and 
circled the CREATE of it again and the sql normal wheel, the triggers 
are working.

Thank you.

-- 
ATT.

Erison Roberto Belon
Técnólogo em processamento de dados
Bacharel em desenvolvimento de software para web
email: nosire@gmail.com
skype: nosireerb
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