Kjell,

>
> ...In SQL Server you generally do this using this syntax
> (non-standard?):
>
> update M
> set ...
> from M
> inner join D on ...
> where ...
>
> What I did was that I accidentally created SQL that in selected more
> than one D record for a few of the M records.

Right. That's why that "multi-table update" syntax isn't standard
and isn't implemented in Firebird.

Best regards,

Ann