crash

crash

SQL Antipatterns, Volume 1: 5th normal form and compound key (page 333)

@billkarwin

You say that the DB is in the 5th normal form if it does not have compound PK.
But in the solution tables you still have compound keys (bug_id, assigned_to) and (account_id, product_id). Are these not counts as compound keys?

First Post!

billkarwin

billkarwin

Author of SQL Antipatterns, Volume 1

Yes, the table in this section has a compound key. A table with no compound key is implicitly in fifth normal form, so that would not be a good example of a table that needs to be fixed to satisfy fifth normal form. The first paragraph should be more clear that only a table that needs to be fixed is shown.

Popular Pragmatic topics Top

New
mikecargal
Title: Hands-On Rust (Chap 8 (Adding a Heads Up Display) It looks like ​.with_simple_console_no_bg​(SCREEN_WIDTH*2, SCREEN_HEIGHT*2...
New
mikecargal
Title: Hands-On Rust (Chapter 11: prefab) Just played a couple of amulet-less games. With a bit of debugging, I believe that your can_p...
New
conradwt
First, the code resources: Page 237: rumbl_umbrella/apps/rumbl/mix.exs Note: That this file is missing. Page 238: rumbl_umbrella/app...
New
joepstender
The generated iex result below should list products instead of product for the metadata. (page 67) iex> product = %Product{} %Pento....
New
rmurray10127
Title: Intuitive Python: docker run… denied error (page 2) Attempted to run the docker command in both CLI and Powershell PS C:\Users\r...
New
dsmith42
Hey there, I’m enjoying this book and have learned a few things alredayd. However, in Chapter 4 I believe we are meant to see the “>...
New
adamwoolhether
Is there any place where we can discuss the solutions to some of the exercises? I can figure most of them out, but am having trouble with...
New
davetron5000
Hello faithful readers! If you have tried to follow along in the book, you are asked to start up the dev environment via dx/build and ar...
New
dachristenson
@mfazio23 Android Studio will not accept anything I do when trying to use the Transformations class, as described on pp. 140-141. Googl...
New

Other popular topics Top

AstonJ
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
New
ohm
Which, if any, games do you play? On what platform? I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
Exadra37
Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...
New
brentjanderson
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
New
AstonJ
Thanks to @foxtrottwist’s and @Tomas’s posts in this thread: Poll: Which code editor do you use? I bought Onivim! :nerd_face: https://on...
New
Exadra37
On modern versions of macOS, you simply can’t power on your computer, launch a text editor or eBook reader, and write or read, without a ...
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
New
wmnnd
Here’s the story how one of the world’s first production deployments of LiveView came to be - and how trying to improve it almost caused ...
New
PragmaticBookshelf
Author Spotlight: Sophie DeBenedetto @SophieDeBenedetto The days of the traditional request-response web application are long gone, b...
New

Latest in PragProg

View all threads ❯