On fre, 2011-08-12 at 16:14 -0400, Robert Haas wrote:
> On Fri, Aug 12, 2011 at 4:11 PM, Peter Eisentraut <peter_e@gmx.net> wrote:
> > "A table is either a base table, a derived table, a transient table, or
> > a viewed table." (SQL/MED adds "foreign table".)
> >
> > Just FYI.
>
> Base table seems clear enough, and a transient table sounds like a
> temporary table, but what is a derived table? Is a viewed table a
> view?
A base table is either a permanent base table or (one of various kinds
of) a temporary base table. A derived table is the result of a table
expression, so this is more of a notional syntactic term. A transient
table is, roughly speaking, OLD or NEW in a trigger. A viewed table is
a view.