Talk:Codd's 12 rules

message: There are 12 rules. Shouldn't the article (albeit not the title) be updated to reflect this, if we're going to include a "rule zero"? Neilc 01:19, 11 Aug 2004 (UTC)
replies: text: Codd himself called them 12 rules, even though there are, in fact, 13 rules. McKay 12:10, 13 September 2006 (UTC)
replies: text: They were called the "12 Rules", but there are 13 of them.  This has been noted in the article now. SqlPac (talk) 03:19, 21 March 2008 (UTC)
thread_title:  13 rules 

message: This article would be a lot more valuable if examples were shown to illustrate why the rules are necessary.  I'll give an example example:
:For Rule 3 (regarding null values) There have been several reports  of law-enforcement agencies designating the use of a value (e.g. "NOTAG", "NO PLATE") on parking tickets to indicate the absence of a license plate on the violator's vehicle. Later, an individual jokingly or inadverdently registers a custom license plate having one of these key values and is inundated with notices regarding unpaid parking tickets.
--Theodore Kloba 16:21, July 21, 2005 (UTC)
: I'm not opposed to having examples on the pages, but I don't think that we want to clutter up the rules more than they already are. Maybe having some sort of summary at the top, and examples at the bottom. If you'd like to organize such an effort feel free. I've a bunch of examples (in SQL Systems mostly), of why violations of any of these rules are very bad. McKay 16:14, 26 July 2005 (UTC)
replies: text: You are suggesting original content, which is not allowed on wikipedia.70.189.92.82 (talk) 22:53, 10 January 2018 (UTC)
thread_title:  Reasons & examples 

message: There seems to be no discussion of Neilc's 2004 comment pointing out that there are actually 13
rules in the article while the article's title is Codd's 12 Rules.  I note that links to
this article from others, e.g. the one defining a true relational database management system, also refer to 12 rules.  This certainly led me to expect to see 12 rules when I clicked on the Codd's 12 Rules hotlink on that page.  I was first startled and then annoyed when I encoun-
tered 13 rules instead of 12.
After looking into this matter, I've concluded that what this article refers to as Rule 1 should
really be called Rule 0, since that is how it is referred to by commentators such as Date and
Hite. I suggest four modifications to the article:  1) The first sentence could be modified to read "Codd's 12 rules are a set of rules proposed by......"; 2) A sentence could be added to
the effect that "While Codd's rules are typically referred to as Codd's 12 Rules, references to
them usually list 13 rules, starting with Rule Zero."; 3) the list of rules should be renumbered
so as to run from Rule 0 through Rule 12; 4) a reference to Codd's 1985 Computerworld articles
(Computerworld October 14th 1985 and Computerworld October 21st 1985) should be added somewhere in
the first or second paragraph. 
I'm writing this as a computer user, not a computing historian or information technologist, so I
will leave it to others to evaluate my comments and make any suitable edits to the article rather
than be presumptuous and actually edit it myself.  --JRamlow 10:55, 13 September 2006 (UTC)
replies: text: The numbering of the rules seems correct, though such an introductary paragraph would be welcome. As would a link or reference to his original work. McKay 12:12, 13 September 2006 (UTC)
replies: text: Modified intro to indicate there are actually 13 rules numbered 0 through 12. SqlPac (talk) 03:21, 21 March 2008 (UTC)
thread_title:  13 Rules Revisited 

message: The sentence "In fact, however, the rules are so strict that even systems whose only interface is the SQL language fail on some of the criteria" seems to be completely out of place here. SQL does not guarantee in any way that the system is relational. It might be a good idea to rephrase that as "In fact, some of today's most popular and sophisticated systems fail on some of the criteria". Rkrush 12:32, 22 October 2006 (UTC)
replies: text: The sentence is original content, I'm removing it.70.189.92.82 (talk) 22:53, 10 January 2018 (UTC)
thread_title:  Reference to SQL 

message: Since the publication of Codd's rules a paper which demonstrated that Rule 6 is undecideable has been written and acknowledged by Codd as being correct. See H. W. Buff: Why Codd's Rule No. 6 Must be Reformulated. SIGMOD Record 17(4): 79-80(1988) and E. F. Codd: Response to "Why Codd's Rule No. 6 Must be Reformulated". SIGMOD Record 18(1): 16(1989). Codd has subsequently issued a major revision to rule 6 which appears in his book on the Relational Model Version 2. 82.37.0.72 18:15, 28 May 2007 (UTC)
replies: text: I don't have my copy handy.  Can someone add it and source it (if it hasn't been yet)? SqlPac (talk) 03:21, 21 March 2008 (UTC)
thread_title:  Rule 6 

message: Even if such repackaged non-relational products eventually gave way to SQL DBMSs, no popular "relational" DBMSs are actually relational, be it by Codd’s twelve rules or by the more formal definitions in his papers, in his books or in succeeding works in the academia or by its coworkers and successors, Christopher J. Date, Hugh Darwen, David McGoveran and Fabian Pascal. Only less known DBMSs, most of them academic, strive to comply. The only commercial example, as of December 2010, is Dataphor.
What is ORACLE or INGRESS then?
Wikipedia's article states it so . . .
I am confused :S  — Preceding unsigned comment added by 117.199.51.138 (talk) 13:36, 30 August 2011 (UTC)
replies: text: SQL is based on relational algebra, but it's far, far from being 100% relational. Also, ORACLE or INGRESS are far, far from being 100% compliant with SQL standard. 93.87.212.7 (talk) 11:05, 3 November 2011 (UTC)
replies: text: Re: The comments above, it's INGRES or Ingres, not INGRESS.  Originally named for the machine where the source for the University Ingres project lived.  The machine was one of the 'painters' systems at UC Berkeley and was named for Jean Auguste Dominique Ingres, a French Neoclassical painter.  The back-formation "INteractive GRaphical Retrieval System" was used in marketing.98.248.42.250 (talk) 03:15, 15 April 2013 (UTC)
thread_title:  no popular "relational" DBMSs are actually relational . . .