Sunday, December 17, 2017

This Week




1. Database truth of the week

"Within the database field, it is common to refer to three “level” of description: conceptual, logical, and physical. Both the logical level and the physical level are formal systems. By contrast, the conceptual level is typically an informal system and refers to the subject of the database.

The conceptual language is a subject language, in the terminology of formal systems. The conceptual level identifies the concepts to be formally represented by the logical and physical levels, and how users think and talk about those concepts. This level corresponds only informally to the so-called “conceptual schema” of earlier approaches to information management, which emphasized the capture of conceptual information using various techniques including diagrams and documentation having various degrees of formality, but not forming a strictly formal system themselves." -- David McGoveran

2. What's wrong with this database picture?


I re-wrote two older debunkings to bring them in line with the McGoveran formalization and interpretation of Codd's true RDM. Re-reads are recommended.
"Can you have 2 tables, VIEWS and DOWNLOADS, with identical structure in a good DB schema (item_id, user_id, time). Some of the records will be identical but their meaning will be different depending on which table they are in. The "views" table is updated any time a user views an item for the first time. The "downloads" table is updated any time a user downloads an item for the first time. Both of the tables can exist without the other ..."
"I have a database for a school ... [with] are numerous tables obviously but consider these:
CONTACT - all contacts (students, faculty) has fields such as LAST, FIRST, MI, ADDR, CITY, STATE, ZIP, EMAIL;
FACULTY - hire info, login/password for electronic timesheet login, foreign key to CONTACT;
STUDENT - medical comments, current grade, foreign key to CONTACT.
Do you think it is a good idea to have a single table hold such info? Or, would you have had the tables FACULTY and STUDENT store LAST, FIRST, ADDR and other fields? ..."

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3. To Laugh or Cry?

"Database design is the structure a database uses to plan, store and manage data. Data consistency is achieved when a database is designed to store only useful and required data ... The outline of the table allows data to be consistent. Cascading also ensures data uniformity ... Optimized relationships ensure efficient database performance ... Overall performance of a database is dependent on the design ... Database normalization, or data normalization, is a technique to organize the contents of the tables for transactional databases and data warehouses ... without normalization, database systems can be inaccurate, slow, and inefficient, and they might not produce the data you expect ... When you normalize a database, you have four goals: arranging data into logical groupings such that each group describes a small part of the whole; ... organizing the data such that, when you modify it, you make the change in only one place; and building a database in which you can access and manipulate the data quickly and efficiently without compromising the integrity of the data in storage ... Sometimes database designers refer to these goals in terms such as data integrity, referential integrity, or keyed data access." --Halil Lacevic, What are the uses or importance of database design? Quora.com


4. Told you so. 


The inevitable consequence of substituting training for education, clearly stated:
  1. There are 56 categories of entries known as Classes.
  2. The competitors (usually around 1500) can enter as many classes as they wish. There are also group classes, for Institutes (groups of Competitors).
  3. The entrants details will arrive in a spreadsheet which I will load into tblCompetitors. The fields are CompetitorNumber, Forename, Surname, InstituteName, InstituteLargeSmall, ClassEntered.
I am reasonably OK with putting the DB together and the SQL queries, but the design is stumping me and there are not a lot of examples on the web for scoring databases." --rslater269, Design Assistance, dbforums.com

5. Publications



Reviews: Craig Mullins, Todd Everett, Toon Koppelaars, Davide Mauri


6. Housekeeping: Using the new DBDebunk search labels


To work around Blogger limitations, the labels are mostly abbreviations or acronyms of the terms listed on the FUNDAMENTALS page. For detailed instructions on how to understand and use the the labels in conjunction with the FUNDAMENTALS page, see the ABOUT page.

 The 2017 and 2016 posts, including earlier posts rewritten in 2017 are relabeled. As other older posts are rewritten, they will also be relabeled, but in the meantime, Blogger search must be used to reach them.



7. Oldie but goodie

When “Fowl” Is All They've Got (July 2005)

8. Elsewhere

9. Of general interest

And Now for Something Completely Different: The PostWest

 

Pinch Me of the Week: 



Must Read of the Week

"While not surprising, it is truly astonishing to see the conflict-of-interest greed monsters who run this country outwardly laugh about how corrupt they are. This video made my blood boil because it’s a perfect look into the psychology of the elite. Our protest is hilarious to them, and criticism of a regulatory agency captured by special interests is something to be mocked. The fact that telecoms essentially dictate the policies meant to keep them in check is a mere detail." --LEAKED: Head Of FCC Mocks Impending Destruction Of The Internet

Dystopia This Week: Societal suicide

 

 

The Decline and Demise of America and Western Civilization

 



Sillicon Valley: Lawless, Mass robbery, mechanism of tyranny and the destruction of free civilized society

 

Facebook
Amazon
Google
Google updates search to lock you into an endless search loop


Fuck the Joos: Anti-Semitism, the myth of a "Palestinian nation" and the "Peace process" delusion


Cowards and antisemites crawl from under their rocks to decry Jerusalem as the capital of the Jews, but they are the ones who have ensured no peace. If you accept Putin's annexation of Crimea, you must take it out on the Joos and Jerusalem.
And the reality check:

Book of the week

Rana Foroohar, MAKERS AND TAKERS: HOW WALL STREET DESTROYED MAIN STREET
Review: When Wall Street Owns Main Street — Literally

Video of the week

Thank you, President Trump


I will not publish or respond to anonymous comments. If you have something to say, stand behind it. Otherwise don't bother, it'll be ignored.



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