Ivan,

> you can kill the application -
> FB server will notice it and cancel the query.

I do use a TCP/IP connection.

However, this morning killing the client application that started the
the heavy task did not release the server: it went on working and
leaving all the other clients on wait, at least for several seconds.

Maybe I was too impatient and should have waited longer ?

I mean: how long does it take to FB to realize that a TCP/IP
connection is lost so that all the tasks belonging to the dead
connection can be stopped ?

Thank you

Duilio