|List:||General Discussion||« Previous MessageNext Message »|
|From:||Frank Bax||Date:||April 27 2005 3:30pm|
|Subject:||Re: why NOT NULL in PRIMARY key??|
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At 11:07 AM 4/27/05, Jigal van Hemert wrote: >So, if we would define that the key entry "0-NULL-Whatever" equals >"0-NULL-Whatever" (which MySQL is capable of if you look at the definition >of UNIQUE indexes with BDB tables) then allowing NULLs as part of a key >entry would not permit duplicate entries. At least not more than allowing >other values. You cannot "define" that those keys are equal, because SQL standard states that "0-NULL-Whatever" is *always* *not-equal* to "0-NULL-Whatever".