Re: Reuse of Subselects

Depend in the exact query, you can do:

SELECT column1, x.c, column1-x.c
FROM table1, (... complicated subselect ...) as x;

The above may not work if they're correlated, so you can try:

SELECT column1, column2, column1-column2
FROM
  (SELECT column1, (... complicated subselect ...) as column2
   FROM table1);

Hope this helps,

On Tue, Feb 17, 2004 at 01:02:43PM +0100, Holger Marzen wrote:
> Hi all,
>
> if I have something like this:
>
> SELECT column1,
>        (... complicated subselect ...),
>        column1 - (... same subselect as above ...)
> FROM table1;
>
> do I really have to rewrite the subselect a 2nd time if I need that
> result in another column's expression?
>
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