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Posted by Jochem Maas on 06/06/05 13:51
Jack Jackson wrote:
> Forgive me if this comes twice: my ISP had a service blackout for three
> hours and I don't know what went:
>
>
> If my last post read (and I see that it did) that I was defending myself
> as opposed to falling ALL OVER my sword, I apologize: allow me to be clear:
>
> No, you're all correct and M. Sokolewicz doubly so: I had
> unintentionally selected fields from the wrong table for no reason other
> than lack of sleep coupled with lack of experience and a desperation to
> try to understand
>
> The problem was that I was pulling data in a manner both useless and
> complex from a thoroughly unnecessary table (I could tell you all why
> but you'll all just laugh at me more)
>
> I am grateful for all the help everyone has offered up to now and hope I
> did not offend - I was trying in my last post to indicate that I was
> an idiot, and it appears I've come off as arrogant. I promise it was not
> my intent!
don't worry - I got the idea that maybe there was some confusion
- nothing else. oh and I don't think anyone is/will laugh at you
(well most of us won't ;-/), we have all been 'there' :-)
so all is well.
>
>
> [Then I wrote::]
>
> Ah. I just remembered one reason I had done it involving the art_id field:
>
> I have more publishers in the db than are currently associated with
> artworks. I don't want a publisher to appear unless there is at least
> one image associated with it. So I did this to avoid having people see a
> link to the Sneezy Acres Tribune only to arrive at the next page and
> see, "There are no images associated with this publisher."
>
>
>
> Jochem Maas wrote:
>
>> Jack Jackson wrote:
>>
>>>
>>>
>>> M. Sokolewicz wrote:
>>>
>>>> Jack Jackson wrote:
>>>>
>>>>> Thanks for all the replies. Jochem, thank you for this code, which
>>>>> will take me all night to understand (though I bet it works). I
>>>>> also note that SELECT DISTINCT worked here, too
>>>>>
>>>>> Also as many of you noticed before me, the art_id was in there as a
>>>>> fly in the ointment.
>>>>
>>>>
>>>>
>>>>
>>>> by that statement I ment the exact same thing Jochem ment in his 2nd
>>>> part; I have NO idea why you're selecting *ANYTHING* from the arts
>>>> table... it's *useless* if you don't need the data...
>>>
>>>
>>>
>>>
>>> Er, yes, that was what I meant: I had unintentionally included that
>>> bit.Thank you for your help.
>>>
>>
>> Er, Jack - your original query was:
>>
>> SELECT art.art_id,art.publisher_id,publisher.publisher_name,
>> FROM art
>> LEFT JOIN publisher
>> ON publisher.publisher_id=art.publisher_id
>>
>> which is a selection on the art table... ( with a typo)
>> if you did:
>>
>> SELECT art.publisher_id,publisher.publisher_name
>> FROM art
>> LEFT JOIN publisher
>> ON publisher.publisher_id=art.publisher_id
>>
>> nothing would change. and if you did:
>>
>> SELECT publisher.publisher_id,publisher.publisher_name
>> publisher
>>
>> i.e. not 'unintentionally' selecting from the arts table.
>> then you would not have had a problem in the first place?!
>>
>> I think I'm missing something ;-)
>>
>
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