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From:Norman Khine Date:July 30 2010 3:11am
Subject:Re: IS NULL returns Empty set, but I have empty items
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thank you, this makes sense.

On Thu, Jul 29, 2010 at 11:29 PM, Dan Nelson <dnelson@stripped> wrote:
> In the last episode (Jul 29), Norman Khine said:
>> I don't know what I am missing, but I have this:
>>
>> mysql> SELECT url FROM product WHERE url IS NULL;
>> Empty set (0.05 sec)
>>
>> mysql> SELECT url FROM product WHERE product_Id = 67;
>> +------+
>> | url  |
>> +------+
>> |      |
>> +------+
>> 1 row in set (0.00 sec)
>>
>> what goes with this, how can i ensure that this is NULL?
>
> Your url may be the empty string "".  If it was really NULL, you would see
> "NULL" in the resultset.  Try
>
> SELECT * FROM product WHERE url=""
>
> --
>        Dan Nelson
>        dnelson@stripped
>
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Thread
IS NULL returns Empty set, but I have empty itemsNorman Khine29 Jul
  • Re: IS NULL returns Empty set, but I have empty itemsAndy Wallace29 Jul
  • Re: IS NULL returns Empty set, but I have empty itemsDan Nelson29 Jul
    • Re: IS NULL returns Empty set, but I have empty itemsNorman Khine30 Jul