Thanks to Helen and Luc I found the problem it was a null value in a
query.

Helen, I removed all the suspend from my execute SP, you mention
masterlinks, I'm not sure what you mean. In a non updatable IBOQuery
I use a

simple join in the sql
select * from spares
join tires on spares.idtire = tires.idtire;

I have nothing in insertsql, editsql, and deletesql
nothing in keylinks, joinlinks should I? and how? is that what you
mean as masterlink?

there are keylinks defined for both tables. what is joinlinks

> 4) You have some strange linking in the dataset, e.g. like a
> mastersource
> with no masterlinks defined; or keylinks and masterlinks defined
> for the
> same pair of dependent sets.
>

again thanks for the help with this matter
Daniel