[SQL] Related table question

[Ruslan Zasukhin]

on 1/18/04 10:31 AM, Eric Forget at forgete at cafederic.com wrote:

>>>           a.RecID not in (select ptr from keyword where name <> 'Me')
>>> 
>>> 
>>> However, I see b) working without understanding it. For me it looks like a
>>> double negation. Maybe there is something about SQL I don't understand.
>> 
>> This is query of kind:
>> 
>>   WHERE fld IN (v1, v2, v3)
>> 
>> Here you do not see problems?
>> 
>> In your query we use subselect to get LIST of values.
>> 
>>   WHERE fld IN (select ptr FROM T ... )
> 
> What I don't understand is why the double negation:
> 
>   a.RecID not in (select ptr from keyword where name <> 'Me')

Ops, really.

It seems we do not need NOT.


-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
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e-mail: ruslan at paradigmasoft.com
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