> >>Syntax:
> >>
> >> CREATE TEMPORARY TABLE <table name> <table contents source>
> >> [ON COMMIT {PRESERVE | DELETE} ROWS]
> >>
> >>
> >
> >CREATE GLOBAL TEMPORARY TABLE
> >
> >for tables that are accessible over connection boundaries.
> >
> What, then, are the semantics? If they're visible across connection
> boundaries, when are they created and when are they destroyed?

According to what I understood, is that there are the
following types of temp tables:

GLOBAL
Permanent tables, but with temporary data (ON COMMIT PRESERVE/DELETE).

LOCAL
Local only to the connection - multiple connections can create the same base
table with the same name. The table gets destroyed upon end of session
(connection), end of transaction or end of module (eg: SP).

With regards,

Martijn Tonies
Database Workbench - developer tool for InterBase, Firebird, MySQL & MS SQL
Server.
Upscene Productions
http://www.upscene.com