General DB Topics - DB Theory

Thread preview

Thread	Last Post	Replies

Beautifiul Mind: Thinking about Dijkstra	30 Apr 2006 21:45 GMT	9
I'm a programmer from the mid 70's. At that time the language of choice was Pascal and I think PL1. Both were very expressive in an algothrimic way. The seminal work was "A Discipline of Programming". And also ""The Elements of Programming Style" ala Strunk and White.
efficient compare	30 Apr 2006 13:06 GMT	41
I have two sets A and B, each containing lots of key/value pairs. I want to compare them, to find out what is missing so that I can transfer whatever is needed from A to B and whatever is needed from B to A such that A=B. Any effective algorithms for that? Where should I look?
Box query	28 Apr 2006 20:17 GMT	37
Given a set of n-dimensional boxes table boxes ( dimension# integer, low integer,
Multiplicity, Change and MV	28 Apr 2006 12:13 GMT	182
Change bothers me. Especially in database schema, and specifically when we want to accomodate change in the cardinalities of the relationships we are modelling. Below I've setup a contrived example of lecturer-course, which a school initially deems to be a highly
IDJIT! Your Data Model Can't Posssibly Work!	28 Apr 2006 11:33 GMT	43
> Transfered here from "Multiplicity, Change and MV" thread (at OP's request). > Bob Badour: Neo, you are so full of sh.t your eyes must be brown. You are an ignorant who doesn't have a clue what he is talking about. ... NIAM, nijssen and halpin. They set the reference point for ...
Reflections of a beautiful mind... Fundamental principle: Separation of Concerns	27 Apr 2006 04:38 GMT	12
Returning to comp.databases.theory and the discussions here has prompted me to delve into the EWD archive at utexas. Like an inexhaustible jewel mine, the archive is full of great riches: gems reflecting a beautiful mind. For instance, re-reading EWD 709:
Has E/R had a negative impact on db?	25 Apr 2006 18:22 GMT	39
Just a thought. I don't like entities. In fact I despise entities, as the enemy of good information philosophy. You see I just don't accept their existence. There is no magical wrapper surrounding some construct that turns it
Relational lattice completeness	23 Apr 2006 20:41 GMT	27
Mikito Harakiri wrote: > Jan Hidders wrote: > > I'm asking the question for a specific model, not in general as you > > did. For example, boolean algebra for boolean value is complete.
Entity Overlap and Relationships	21 Apr 2006 19:08 GMT	20
1. What is the "industry best practice" in the following situation: Say there are 3 types of entities {Entity1, Entity2, Entity3} Each Entity type has unique attributes and similar ones. For the attributes that are unique to each Entity it is easy (either
THe OverRelational Manifesto (ORM)	21 Apr 2006 16:23 GMT	70
" the The Third Manifesto is formal and logical. However, The OverRelational Manifesto (ORM) cannot unconditionally accept the claims of the The Third Manifesto, because, in our opinion, the premises, which are its basis, are incomplete. Recall that, answering
Reinventing the TransRelational Model?	20 Apr 2006 22:10 GMT	15
I came across this article by Stonebraker, et.al. the other day that presents and discusses a "column-based" DBMS architecture: http://www.vldb2005.org/program/paper/thu/p553-stonebraker.pdf There are certainly areas that seem reminiscent of what was espoused as
Best way to set up	20 Apr 2006 14:39 GMT	3
Sorry, wasn't sure really how to word the subject properly. I am wondering the best way to set up some tables in MySQL. What I want is to enable users to keep song favorites - easy enough store the song's id in the users favorites table. From there though, I want to display say ...
Order By	20 Apr 2006 06:25 GMT	4
I have a query where i am returning a property which is a string. I am trying to perform the following: *NB: Note the position of of the try_itemcode value 002240-10 The sort order i want to achieve:
IDIOT! Your Data Model Can't Possibly Work!	16 Apr 2006 18:23 GMT	1
> Transfered here from "Multiplicity, Change and MV" thread (at OP's request). > Bob Badour: Neo, you are so full of sh.t your eyes must be brown. You are an ignorant who doesn't have a clue what he is talking about. ... NIAM, nijssen and halpin. They set the reference point for ...
Modeling zip+4	14 Apr 2006 00:33 GMT	1
What is a "right way" to model (logical model) a postal code, including zip+4? Because the zip+4 was an add-on and is not always used for mailing or analytical purposes, I would think that attributes of postCode (char 6) and zip4 (char 4) might be typical. Would that be