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]
