Re: Basic SQL join question

On Fri, 31 Jan 2003, Jean-Christian Imbeault wrote:

> Sorry for this simple question but I can't seem to get Postgres to do
> what I want ...
>
> I want to get the concatenation of 2 or more tables with absolutely
> nothing in common. How can I do this?
>
> For example
>
> Table a:
>
>    a
> -----
>   a1
>   a2
>   a3
>
> Table b:
>
>    b
> -----
>   b1
>   b2
>
> Table c:
>
>    c
> -----
>   c1
>   c2
>   c3
>   c4
>
> What is the proper SQL to return:
>
>    a |  b |  c
> ---------------
>   a1   b1   c1
>   a2   b2   c2
>   a3        c3
>             c4
>

I can't think of a real SQL solution (although there might be
one).  A pl function could do this but it'd be a little wierd
probably.  Note that unless those tables are really selects with
ordering the results are pretty indeterminate and probably
meaningless since order is not guaranteed.