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From:Jay Blanchard Date:April 26 2005 3:17pm
Subject:RE: why NOT NULL in PRIMARY key??
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[snip]
The same is true for any other value... Now that the columns have a NOT
NULL
constraint the records that previously contained NULL now hold '0'.

x y
x 0
x z
x 0

Now, how do you uniquely identify the 2nd and 4th rows?
[/snip]

The database would have thrown an error when you tried to create row 4.
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