You can use the COALESCE function, like this:
INSERT INTO table (idthread, idsection,txt)
VALUES (
COALESCE((SELECT max(idthread)+1 FROM table WHERE idsection =
'CZE'),1), 'CZE',
'sample text')
);
This function returns the first of its argument that is not null. If your
query returns no value, the second argument (in this case, the number
"1").
Marcelo Soares
Informática - Master Hotéis
ICQ Externo: 19398317
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> I need to insert a value = max(value)+1, where max is a select limited
> by a 'where' clause. Like this:
>
> INSERT INTO table (idthread, idsection,txt)
> VALUES (
> (SELECT max(idthread)+1 FROM table WHERE idsection = 'CZE'), 'CZE',
> 'sample text')
> );
>
> This works fine, except when the result of SELECT is empty - which is
> true when the table is empty.
>
> Is it possible to create a "SELECT max(idthread)+1 FROM table WHERE
> idsection = 'CZE';" that will return value 1 instead of value None if
> the SELECT has no results?
>
> --
> Milos Prudek
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