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From:beacker Date:April 30 2005 3:27am
Subject:Re: why NOT NULL in PRIMARY key??
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Jigal van Hemert <jigal@stripped> writes:
>> Because the SQL standard says so.
>
>A true observation, but still no explanation or reason why ;-P
>MySQL doesn't follow the standard in every situation, so that's not an
>excuse... (no offense!)
>There must be a good reason other than "because our ancestors always did it
>this way".

Let's look at it from a pure logic point of view.  Given the table:

create table a (
   b int not null,
   c int null
   primary_key(b,c)
);

With values:
	1	null
	1	null

Logically these are unique records under the standard proviso that
null != null.  Yet how could I uniquely identify the first row to delete
that row?
             Brad Eacker (beacker@stripped)
Thread
why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies26 Apr
  • Re: why NOT NULL in PRIMARY key??Jochem van Dieten26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
  • Re: why NOT NULL in PRIMARY key??Harald Fuchs26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??SGreen26 Apr
      • Att. Shawn GreenJigal van Hemert2 May
  • Re: why NOT NULL in PRIMARY key??Dawid Kuroczko26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??Jochem van Dieten26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??Paul DuBois26 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies26 Apr
  • Re: why NOT NULL in PRIMARY key??Mikhail Entaltsev26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
  • Re: why NOT NULL in PRIMARY key??Harald Fuchs26 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert27 Apr
    • Re: why NOT NULL in PRIMARY key??Peter Brawley27 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert27 Apr
    • Re: why NOT NULL in PRIMARY key??Frank Bax27 Apr
    • Re: why NOT NULL in PRIMARY key??Peter Brawley27 Apr
    • Re: why NOT NULL in PRIMARY key??Joerg Bruehe27 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert28 Apr
RE: why NOT NULL in PRIMARY key??Jay Blanchard26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??Paul DuBois26 Apr
  • RE: why NOT NULL in PRIMARY key??Frank Bax26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??Paul DuBois26 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies26 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert26 Apr
    • Re: why NOT NULL in PRIMARY key??Paul DuBois26 Apr
    • Re: why NOT NULL in PRIMARY key??Peter Brawley26 Apr
RE: why NOT NULL in PRIMARY key??emierzwa26 Apr
  • RE: why NOT NULL in PRIMARY key??SGreen26 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies26 Apr
RE: why NOT NULL in PRIMARY key??Jay Blanchard26 Apr
  • Re: why NOT NULL in PRIMARY key??Dawid Kuroczko27 Apr
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies27 Apr
RE: why NOT NULL in PRIMARY key??emierzwa26 Apr
Re: why NOT NULL in PRIMARY key??beacker30 Apr
  • Re: why NOT NULL in PRIMARY key??Jigal van Hemert1 May
  • Re: why NOT NULL in PRIMARY key??Martijn Tonies1 May