Re: building sets in SQL92

"James Chapman" <Jim.Chapman_at_nospam.elsegundoca.ncr.com> wrote in <3b1bcb35$1_at_rpc1284.daytonoh.ncr.com>:

>Sure. The syntax is standard SQL. It does depend on an
>extra-syntactical assumption -- that there exists some table named DUAL,
>and that it contains exactly one row. Some implementations may have
>such a table by default, but,
>of course, it would be trivial to satisfy the assumption in any standard
>SQL implementation:
>
>create table DUAL (dummy integer);
>insert into DUAL values(1);

I'm just curious; what is dual about a table with a single column and a single row?

--
/Per Schröder
http://developer.mimer.com