Reply to Re: Retrieve One Row Of MySQL

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Posted by Gary L. Burnore on 10/04/07 02:33

On Wed, 3 Oct 2007 21:16:22 -0400, "Shelly"
<sheldonlg.news@asap-consult.com> wrote:

>
>"axlq" <axlq@spamcop.net> wrote in message
>news:fe1auv$g0r$1@blue.rahul.net...
>> In article <1191424134.543150.96700@o80g2000hse.googlegroups.com>,
>> Claudio Corlatti <corlatti@gmail.com> wrote:
>>>well i didn't understand your question very well, but i suppose that
>>>you want to obtain just one row from the table "colors".
>>>
>>>to do that you need to add a "where" clause in your mysql query, for
>>>instance "select * from colors where idColor=1"
>>
>> That will work, but a LIMIT should also be specified for efficiency.
>> The query "SELECT * FROM MyColorTable WHERE ColorID=26 LIMIT 1" will
>> cause MySQL to stop searching the table as soon as one row is found.
>> Otherwise it will keep searching for other rows with ColorID=26.
>>
>> -A
>
>WHY does the OP wand to stop at one? Is this simply check for the
>existinance of some value in a particular field/ If that is so, why not use
>the COUNT operator in the sql call?

Maybe because if you've got hundreds of thousands of rows to count
and, instead, you want to stop after looking at only one to see if the
table is non-empty, you'd save some processing time?

>
>Shelly
>
--
gburnore at DataBasix dot Com
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