edg@squid.rtech.com (Ed Goldman) (09/28/88)
In article <987@mdbs.UUCP> kbc@mdbs.UUCP (Kevin Castleberry) writes: > >MDBS III (a post-relational high performance dbs) ^^^^^^^^^^^^^^^ Sheesh, c'mon you you guys. There's nothing relational about MDBS III and to imply so in your tag is misleading. I might go for "extended- CODASYL", but trying to make a relational association is pretty ludicrous. I have used the product (on PC) and like it (aside from the pricing and licensing policies). Call your product what it is and let its arch- itecture stand on its own merits. sorry. flame off. -edg-
fst@mcgp1.UUCP (Skip Tavakkolian) (10/02/88)
In article <2452@rtech.rtech.com>, edg@squid.rtech.com (Ed Goldman) writes: > In article <987@mdbs.UUCP> kbc@mdbs.UUCP (Kevin Castleberry) writes: > >MDBS III (a post-relational high performance dbs) ^^^^^^^^^^^^^^^ > Sheesh, c'mon you you guys. There's nothing relational about MDBS III [deleted] > -edg- I have had this question for about two years know; The first time I ever saw the term ``post-relational'', was in an ad for MDBS. It said it was a ``post-relational, network-type database''. Although I am not a newcomer to the database arena, I've never been able to get a definition on this. Could some one please describe ``post-relational''? Sincerely -- Fariborz ``Skip'' Tavakkolian UUCP ...!uw-beaver!tikal!mcgp1!fst UNIX is a registered trademark of AT&T
broman@schroeder.nosc.mil (Vincent Broman) (10/03/88)
From very limited reading I gather that MDBS is an "extended-network" DBMS, based on DB theory more recent than the network and relational DB models, both of which originated around 1970. So "post-relational" means a model developed after the "relational" model. Supposedly, this would be a superior model, but not a descendent. Vincent Broman, code 632, Naval Ocean Systems Center, San Diego, CA 92152, USA Phone: +1 619 553 1641 Internet: broman@nosc.mil Uucp: sdcsvax!nosc!broman
berlin@bu-cs.BU.EDU (David K. Fickes) (10/04/88)
The question is "what is a "post-relational" system? At this point, I would say great marketing tool because this comes up every once in a while on the net and we all get to discuss it.... I can only assume it to be a very misleading (and intentionally at that) and rather egotistcal since they are attempting to say "better than" relational... Does anyone actually use (or has used) this stuff? - david -- ============================================================================== David K. Fickes Center for Einstein Studies/Einstein Papers Project UUCP: ...harvard!bu-it!berlin Boston University OTHERWISE: berlin@bu-it.bu.edu 745 Commonwealth Avenue PHONE: (617) 353-9249 (617) 277-9741 Boston, MA 02215
ph@uowcsa.cs.uow.oz (Phillip Herring) (10/04/88)
In article <1597@mcgp1.UUCP>, fst@mcgp1.UUCP (Skip Tavakkolian) writes: > In article <2452@rtech.rtech.com>, edg@squid.rtech.com (Ed Goldman) writes: > > In article <987@mdbs.UUCP> kbc@mdbs.UUCP (Kevin Castleberry) writes: > > >MDBS III (a post-relational high performance dbs) > ^^^^^^^^^^^^^^^ > > Sheesh, c'mon you you guys. There's nothing relational about MDBS III > [deleted] > > -edg- > > I have had this question for about two years know; The first time I ever > saw the term ``post-relational'', was in an ad for MDBS. It said > it was a ``post-relational, network-type database''. Although I am not a > newcomer to the database arena, I've never been able to get a definition > on this. Could some one please describe ``post-relational''? The above definition (post-relational, network-style) strikes me as bizarre! The relational model replaced to network (CODASYL) model as the industry standard many years ago - advertising a new DBMS as such strikes me as counterproductive. The explanantion that springs to mind, however, is that they are referring to a system that uses either the E-R (entity-relationship), or semantic net model. Both have more in common with the network model than the relational (e.g. direct m:n modelling). The E-R model in particular is the designer's choice for conceptual modelling, and has been used in several new DBMS's. Another possibility that springs to mind is that the DBMS uses the object-oriented paradigm; this is where the new generation of Ingres (Postgres) is headed. All in all, however, 'post-relational' refers to the DBMS using some more adavanced data model; usually E-R or object- oriented. Phil. /*-------------------------------------------------------------------------- Rev. Dr. Phil Herring, Dept. of Computing Science, University of Wollongong ph@uowcsa.oz I've been wrong before, I'll be wrong again - that's the only thing my employer will agree with. --------------------------------------------------------------------------*/
pavlov@hscfvax.harvard.edu (G.Pavlov) (10/05/88)
In article <BROMAN.88Oct3102719@schroeder.nosc.mil>, broman@schroeder.nosc.mil (Vincent Broman) writes: > From very limited reading I gather that MDBS is an "extended-network" > DBMS, based on DB theory more recent than the network and relational > DB models, both of which originated around 1970. > What reading ? The only usage of "post-relational" that I have seen is as a general adjective and in MDBS ads. I would really like to know. What does "extended network" mean ? E.g., what characteristics does it have that are not dealt with or ar part of the network model ? Don't get me wrong. There are aspects of the relational model that cause us considerable grief (actually, not the model itself, but the rules gov- erning the design of languages used to operate on it). But it allows us to do things that were virtually impossible for us before. greg pavlov, fstrf, amherst, ny
jam@bunker.UUCP (James A. McFarland) (10/05/88)
In article <1597@mcgp1.UUCP> fst@mcgp1.UUCP (Skip Tavakkolian) writes: >In article <2452@rtech.rtech.com>, edg@squid.rtech.com (Ed Goldman) writes: >> In article <987@mdbs.UUCP> kbc@mdbs.UUCP (Kevin Castleberry) writes: >> >MDBS III (a post-relational high performance dbs) > ^^^^^^^^^^^^^^^ >> Sheesh, c'mon you you guys. There's nothing relational about MDBS III >[deleted] >> -edg- > >I have had this question for about two years know; > [more desires to know deleted ...] > >Fariborz ``Skip'' Tavakkolian > DISCLAIMER: I am not an expert, and only the source (folks at mdbs) can say for sure. (NOTE: I am not sure why Kevin C. of mdbs technical support [[hi kevin, it's jim from your math class]] has not periodically posted the answer to this question, but currently I think their usenet node is off-line for a short time) As far as I have been able to rationalize it, the term "post-relational" is supposed mean NOT relational. The name is supposed to imply that it is conceptually a successor to relational technology. In other words, "after-relational." An analogy might be: "relational" is to "post-relational" as "3GL" is to "4GL" (be careful here, we are not talking about 3GL's and 4GL's, we are talking about databases) Kevin, if you are out there, please correct or confirm my theories. -jam -- {decvax|yale|philabs}!bunker!jam \ j \ 203/337-1521 \ a \ james mcfarland \ m \ bunker ramo, an olivetti company
broman@schroeder.nosc.mil (Vincent Broman) (10/05/88)
What reading? All I know about this is in: Bonczek, Holsapple, and Whinston, Micro Database Management: practical techniques for application development, Academic Press (HBJ), 1984. I only had time to skim some highlights, much of which went right over my head. :-) The authors use the term "postrelational" to describe the "extended-network" approach, which they contrast with the older hierarchical, shallow network, CODASYL network, and relational approaches. They use MDBS III prominently in the book and in an associated course, sounding almost commercial in their promotion thereof. There is an appendix devoted to debunking current "myths" about relational technology and its being the summit of DBMS evolution, pointing out how other approaches have its same advantages of clear theory, nonprocedural access, etc. Unfortunately, the juicy details about how extended networks beautifully support representation of many-to-many relations I didn't get to. Any one else study this? Vincent Broman, code 632, Naval Ocean Systems Center, San Diego, CA 92152, USA Phone: +1 619 553 1641 Internet: broman@nosc.mil Uucp: sdcsvax!nosc!broman
vfm6066@dsacg3.UUCP (John A. Ebersold) (10/06/88)
From article <25195@bu-cs.BU.EDU>, by berlin@bu-cs.BU.EDU (David K. Fickes): > The question is "what is a "post-relational" system? > > Does anyone actually use (or has used) this stuff? I used MDBS-III a few years ago for about nine months. It is a network model DBMS. John Ebersold osu-cis!dsacg1!dsacg3!jebersold
edg@squid.rtech.com (Ed Goldman) (10/07/88)
In article <BROMAN.88Oct5090037@schroeder.nosc.mil> broman@nosc.mil writes: >What reading? All I know about this is in: > Bonczek, Holsapple, and Whinston, > Micro Database Management: practical techniques for application development, > Academic Press (HBJ), 1984. > [stuff deleted] ... >They use MDBS III prominently >in the book and in an associated course, sounding almost commercial >in their promotion thereof. I believe Holsapple is/was the president of MDBS or the founder or something like that I can't remember exactly. I'm not sure sure about the other 2 but I wouldn't be suprised at an MDBS association there either. >Unfortunately, the juicy details about how extended networks beautifully >support representation of many-to-many relations I didn't get to. > >Any one else study this? I can't say I've read the book, but I have developed an MDBS III application. It's been awhile since I was involved with this network DBMS stuff, but it seems to me the extensions to CODASYL in MDBS III involved the features of creating many-to-many sets and recursive sets. Also there's security and validation features which may go beyond a strict CODASYL system, but I'm not well-versed enough in CODASYL to say fer sure. All-in-all MDBS III is a pretty nice DBMS, but it really depends on what on what your system requires. My opinion was that its pretty fast, but rigid. Rigid in the sense that you must account for your db structure in the code and in the sense that on the fly queries are tougher (than relational) if not impossible. To answer a previous poster: MDBS is not E-R (if E-R is what you're looking for you may want to check out ZIM). -edg-
pavlov@hscfvax.harvard.edu (G.Pavlov) (10/09/88)
In article <BROMAN.88Oct5090037@schroeder.nosc.mil>, broman@schroeder.nosc.mil (Vincent Broman) writes: > What reading? All I know about this is in: > Bonczek, Holsapple, and Whinston, > Micro Database Management: practical techniques for application development, > > ......... They use MDBS III prominently > in the book and in an associated course, sounding almost commercial > in their promotion thereof. ^^^^^^^^^^^^^^^^^^^^^^^^^^ > That should have given you a clue where these people were collecting their rent money. greg pavlov, fstrf, amherst, ny
jam@bunker.UUCP (James A. McFarland) (10/11/88)
In article <2477@rtech.rtech.com> edg@squid.UUCP (Ed Goldman) writes: >In article <BROMAN.88Oct5090037@schroeder.nosc.mil> broman@nosc.mil writes: >>What reading? All I know about this is in: >> Bonczek, Holsapple, and Whinston, >> Micro Database Management: practical techniques for application development, >> Academic Press (HBJ), 1984. >> [stuff deleted] ... >>They use MDBS III prominently >>in the book and in an associated course, sounding almost commercial >>in their promotion thereof. > >I believe Holsapple is/was the president of MDBS or the founder or something >like that I can't remember exactly. > Just to clear things up: Whinston was the founder of mdbs, Inc. It was his idea, and with a few other people, he made it work. He is not the current president of the company. Holsapple did much lecturing on their behalf, but I don't think he ever had a formal position with the company. Bonczek never held a postion with mdbs. [[someone correct me if I'm wrong...]] -jam -- {decvax|yale|philabs}!bunker!jam \ j \ 203/337-1521 \ a \ james mcfarland \ m \ bunker ramo, an olivetti company