Begging to differ, no vendor that I'm aware of claims to be compliant with a paper or textbook. They tend to comply with an adopted standard such as:
ANSI/ISO/IEC 9075-1(through 5):1999 ISO/IEC 9075-1(through 5):1999 Collectively known as SQL:1999. While I'd offer that MySQL *is* a relational database, (even though I'm very new to the environment); I think there's some ways to go before MySQL has core compatibility with SQL:1999. That's what's more important to me, the adoption of accepted standards. ---------------------------------------------------------------------- Michael Brando Senior Manager of Engineering Applied Biosystems 3833 North First Street San Jose, CA 95134-1701 > -----Original Message----- > From: Heikki Tuuri [mailto:[EMAIL PROTECTED] > Sent: Tuesday, October 28, 2003 12:29 PM > To: [EMAIL PROTECTED] > Subject: Re: Is MySQL Relational? (was: Foreigner keys in MySQL?) > > Hi! > > For decades, people have debated in comp.databases.theory and elsewhere how > a 'relational database' should be defined. > > Codd's original 1970 paper sketches the relational algebra as a query > language of a relational database, though Codd is not very precise about > what the query language exactly should be. The paper also mentions integrity > constraints. Relations in the 1970 paper are defined as mathematical sets, > that is, no duplicate rows in tables or any query results are allowed. > > Thus, no SQL database is Codd-1970-relational, because SQL allows duplicate > rows. > > Codd's 12 rules, from about 1987, demand that a 'relational database' must > satisfy several strict conditions. For example, any view 'theoretically > updateable should be updateable with the data manipulation language'. > > No existing database is even close to being Codd-12-relational. > > On the other hand, for example, Elmasri and Navathe in their university > textbook define a 'relational database' less strictly, and mention Microsoft > Access and Oracle as examples of an 'RDBMS'. > > Thus, MySQL apparently is Elmasri-Navathe-relational, but not > Codd-1970-relational. The same holds for DB2, Oracle, and MS SQL Server. > > Best regards, > > Heikki Tuuri > Innobase Oy > http://www.innodb.com > Foreign keys, transactions, and row level locking for MySQL > InnoDB Hot Backup - hot backup tool for InnoDB which also backs up MyISAM > tables > Order MySQL technical support from https://order.mysql.com/ > > > > ----- Original Message ----- > From: "Saqib Ali" <[EMAIL PROTECTED]> > Newsgroups: mailing.database.myodbc > Sent: Tuesday, October 28, 2003 10:10 PM > Subject: RE: Is MySQL Relational? (was: Foreigner keys in MySQL?) > > > > so funtions that can be performed by relation algebra are a subset of the > > functions performed by a relational database? > > > > however isn't it required for a relational database to perform all the > > functions of relation algebra? > > > > > > Saqib Ali > > --------- > > http://validate.sourceforge.net <--- XHTML/HTML/DocBook Validator > > > > On Tue, 28 Oct 2003, Jon Frisby wrote: > > > > > No. Codd's rules defining what is a relational database are more > > > specific than relational algebra can express. Essentially the > > > requirements to be a relational database are a superset of the > > > operations defined by relational algebra. > > > > > > -JF > > > > > > > -----Original Message----- > > > > From: Saqib Ali [mailto:[EMAIL PROTECTED] > > > > Sent: Tuesday, October 28, 2003 8:47 AM > > > > To: [EMAIL PROTECTED] > > > > Cc: [EMAIL PROTECTED] > > > > Subject: Re: Is MySQL Relational? (was: Foreigner keys in MySQL?) > > > > > > > > > > > > a question... > > > > > > > > is any DB that complies to the "Relational Algebra" a > > > > "Relational DB"??? > > > > > > > > Saqib Ali > > > > --------- > > > > http://validate.sourceforge.net <--- XHTML/HTML/DocBook Validator > > > > > > > > On Tue, 28 Oct 2003 [EMAIL PROTECTED] wrote: > > > > > > > > > > > > > > I tend to agree with the past two posts that mysql is in > > > > fact relational, > > > > > and would like to add that if we are going to make blanket > > > > statements that > > > > > something IS or IS NOT that we qualify our responses. > > > > personlly i would > > > > > like to know why Martijn views it as being a non relational > > > > db, without > > > > > argument. If you just say its so, why am is supposed to take that > > > > > statement over those that provide a full email of text like > > > > bluejack or > > > > > John that provided additional information via a link. > > > > > > > > > > Just saying No, to a question like that does not lend to > > > > learning only to > > > > > confusion. > > > > > > > > > > sorry about the mini rant.... > > > > > jeff > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > bluejack > > > > > <[EMAIL PROTECTED] To: > > > > [EMAIL PROTECTED] > > > > > om> cc: > > > > > Subject: Is > > > > MySQL Relational? (was: Foreigner keys in MySQL?) > > > > > 10/28/2003 11:38 > > > > > AM > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > 10/28/03 8:11:16 AM, "Martijn Tonies" <[EMAIL PROTECTED]> wrote: > > > > > > > > > > >> > > > > > >> If you are trying to determine whether MySQL is a > > > > relational database, > > > > > >> the answer is yes. > > > > > > > > > > > >Ehm... the answer is "no". > > > > > > > > > > > >It's getting better, that's for sure. > > > > > > > > > > MySQL may or may not conform to some standard or another, and it may > > > > > or may not perform the tasks that you, personally, want it to, but > > > > > in fact it *is* a relational database, as opposed to a flat file or > > > > > an object database. > > > > > > > > > > I recommended the questioner evaluate her needs against MySQL's > > > > > available feature set, because if you are used to Oracle (or some > > > > > other robust, commercial relational database) you may be surprised > > > > > at some of the differences or absences in MySQL. > > > > > > > > > > But the questioner made it seem as though she was really just > > > > > trying to get a feel for the basics scope of MySQL, and in that > > > > > context, yes, MySQL is designed to a implement a relational > > > > > database model as opposed to some other fundamental type of > > > > > database. > > > > > > > > > > So, what's your laundry list of things MySQL should do? > > > > > > > > > > --bluejack > > > > > > > > > > > > > > > > > > > > -- > > > > > MySQL General Mailing List > > > > > For list archives: http://lists.mysql.com/mysql > > > > > To unsubscribe: > > > > http://lists.mysql.com/mysql?> [EMAIL PROTECTED] > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > MySQL General > > > > Mailing List > > > > > For list archives: http://lists.mysql.com/mysql > > > > > To unsubscribe: > > > > http://lists.mysql.com/mysql?> [EMAIL PROTECTED] > > > > > > > > > > > > > > > > > > -- > > > > > > > > MySQL General Mailing List > > > > > > > > For list archives: http://lists.mysql.com/mysql > > > > To unsubscribe: > > > > http://lists.mysql.com/mysql?> [EMAIL PROTECTED] > > > > > > > > > > > > > > > > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
