>> You are correct - when I shutdown the server after index deletion, the
>> error disappears. Now I wonder - can I somehow invalidate the metadata
>> cache using SQL, or possibly using API itself? My servers are not always
>> easily accessible for shutdown and restart.
>>
>
> Detaching all current sessions (for that database) should do the trick, this
> will unload the database on the server and therefor clear the metadata
> cache.
>

That seems not to be the case - my update script is run by one
application, and the procedure is executed by another application. As
far as I know, at the moment of the update there is just one connection
to the server, the one that performs the update. Other connections start
only after the update connection ends (with a delay of at least a few
seconds).

> It's always a bad idea to do metadata changes while applications are still
> running.
>

Indeed. That's why I don't do it.

Pepak