This query does not make sense to me.
Why would you create an updatable subquery just to get the highest value?
Maybe you are trying to achieve something other than what the query
suggest. You wou care to put in words what you want to do?
JLL
Markus Bertheau wrote:
> Hi,
>
> why is the following query not allowed:
>
> SELECT MAX(position) FROM (SELECT position FROM classes WHERE name =
> 'foo' FOR UPDATE OF classes) AS foo
>
> It's clear which rows should be locked here, I think.
>
> Thanks
>