Re: Operator Precedence problem?

The ANSI/ISO standard specifies that NOT has the highest priority, then
AND and finally OR.

--
Jesus Aneiros Sosa
mailto:aneiros@jagua.cfg.sld.cu
http://jagua.cfg.sld.cu/~aneiros

On Sat, 12 Aug 2000, Philip Warner wrote:

> 
> I have a peculiar problem that I can't reproduce on a trivial database:
> 
> select product, priority, count(*) as completed from issue 
> where
>     product = 'DIS' 
>     and create_date < '1-Aug-2000' and finish_date >= '1-Aug-2000' or
> finish_date is null
> group by product, priority;
> 
> This produces a list of all products - not just 'DIS'. If I put the last
> two clauses in parnthesis, then it works as expected:
> 
> select product, priority, count(*) as completed from issue 
> where
>     product = 'DIS' 
>     and create_date < '1-Aug-2000' and (finish_date >= '1-Aug-2000' or
> finish_date is null)
> group by product, priority;
> 
> Which makes me think that the precedence of 'or' is not what I expected. Is
> this a feature? If so, the fact that I get precisely the opposite behaviour
> in simple test databases must be a bug, I think.
> 
> Any help or explanation would be appreciated...
> 
> 
> 
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