Re: ADQL/XML non compliance with SQL?

From: Clive Page <cgp-at-star.le.ac.uk>
Date: Mon, 9 Feb 2004 15:08:59 +0000 (GMT)


On Mon, 9 Feb 2004, Martin Hill wrote:

> WHERE (f OR f) AND (t OR t) = f
>
> is different from
>
> WHERE f OR (f AND t) OR t = t

As far as I can discover, the AND operator has higher precedence than OR in SQL, as it does in most languages.

(I just tried to do a Google search on the operators AND and OR and it didn't get me anywhere, I suppose I should have expected that :-).

> On another point, isn't XOR a standard SQL boolean operator?

Not as far as I can tell from DBMS manuals that I've looked at, but I don't have access to an SQL Standard here.

-- 
Clive Page
Dept of Physics & Astronomy,
University of Leicester,    Tel +44 116 252 3551
Leicester, LE1 7RH,  U.K.   Fax +44 116 252 3311
Received on 2004-02-09Z16:09:22