> there is other question - what is effect of ALTER TABLE of global temp table on
> instances of this table in active sessions?
As I said, we need to first agree on the behaviors of the existing commands. I can think of two options now for ALTER TABLE: 1) only allow ALTER TABLE when there is no other active sessions (this is how Oracle deals with it.) 2) handle it as if session copies inherit from the global copy and ALTER TABLE executes on the global copy.