Alban Hertroys wrote:
> Unfortunately, I do not own a copy so I can't verify. If anyone
> who does own a copy could confirm or even quote the relevant
> section, that would be great.
I have a copy of The RELATIONAL MODEL for DATABASE MANAGEMENT,
VERSION 2 (RM/V2), by E. F. Codd, Copyright 1990,
On Sun, 2015-01-25 at 14:09 +0100, Alban Hertroys wrote:
> >> The theory got me intrigued. google
> >> (http://en.wikipedia.org/wiki/Codd%27s_12_rules) says:
> >> rule 3: "systematic treatment of null values"; hmmm this is a little
> >> broader then "support for null". I would think, that:
>> The theory got me intrigued. google
>> (http://en.wikipedia.org/wiki/Codd%27s_12_rules) says:
>> rule 3: "systematic treatment of null values"; hmmm this is a little
>> broader then "support for null". I would think, that:
>> 1. if a sequence of "update XX set fk_field=null; then delete Y
