douglasshuang

douglasshuang

High Performance PostgreSQL for Rails: Off-by-one length bug in `SCRUB_EMAIL` (page 52)

Hi @andatki,

This is a follow-up to my previous error report, High Performance PostgreSQL for Rails: Confusing `SUBSTR` arguments in `SCRUB_EMAIL` (page 52). The + 1 after GREATEST(…) was necessary when we were passing 0 as the start index to SUBSTR, but now it’s incorrect and results in a scrubbed email address that is one character too long when the original email username has a length greater than or equal to 5. The example on Page 53 actually demonstrates the bug:

SELECT SCRUB_EMAIL('bob-and-jane@gmail.com');
-- scrub_email
-- ------------------------
-- 2bffb502c463@gmail.com

“bob-and-jane@gmail.com” has length 22, whereas “2bffb502c463@gmail.com” has length 23:

owner@localhost:5432 rideshare_development# SELECT LENGTH('bob-and-jane@gmail.com'), LENGTH(SCRUB_EMAIL('bob-and-jane@gmail.com'));
 length | length
--------+--------
     22 |     23
(1 row)

Thank you,

Doug

First Post!

andatki

andatki

Author of High Performance PostgreSQL for Rails

Hi @douglasshuang Shoot! Well unfortunately it’s too late to fix it in the book. I do have the functions or similar ones here in the Rideshare source. If you’d like to create a PR it might help someone else who goes looking. This thread may also help them find it. rideshare/db/functions at main · andyatkinson/rideshare · GitHub Fortunately since the intent was to have similar sized data but scrubbed, if it’s one character too long of random text, at least it will be uniformly 1 character too long, so the proportions of lengths should stay the same. Thanks for continuing to be a reader and bug finder. This forum had gotten pretty quiet lately! :slight_smile:

Where Next?

Popular Pragmatic Bookshelf topics Top

jimschubert
In Chapter 3, the source for index introduces Config on page 31, followed by more code including tests; Config isn’t introduced until pag...
New
brianokken
Many tasks_proj/tests directories exist in chapters 2, 3, 5 that have tests that use the custom markers smoke and get, which are not decl...
New
jdufour
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
New
herminiotorres
Hi! I know not the intentions behind this narrative when called, on page XI: mount() |> handle_event() |> render() but the correc...
New
jgchristopher
“The ProductLive.Index template calls a helper function, live_component/3, that in turn calls on the modal component. ” Excerpt From: Br...
New
jskubick
I found an issue in Chapter 7 regarding android:backgroundTint vs app:backgroundTint. How to replicate: load chapter-7 from zipfile i...
New
brunogirin
When running tox for the first time, I got the following error: ERROR: InterpreterNotFound: python3.10 I realised that I was running ...
New
oaklandgit
Hi, I completed chapter 6 but am getting the following error when running: thread 'main' panicked at 'Failed to load texture: IoError(O...
New
taguniversalmachine
Hi, I am getting an error I cannot figure out on my test. I have what I think is the exact code from the book, other than I changed “us...
New
SlowburnAZ
Getting an error when installing the dependencies at the start of this chapter: could not compile dependency :exla, "mix compile" failed...
New

Other popular topics Top

Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
AstonJ
There’s a whole world of custom keycaps out there that I didn’t know existed! Check out all of our Keycaps threads here: https://forum....
New
Maartz
Hi folks, I don’t know if I saw this here but, here’s a new programming language, called Roc Reminds me a bit of Elm and thus Haskell. ...
New
foxtrottwist
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
New
New
PragmaticBookshelf
25 puzzles that will make you a better C programmer by challenging your knowledge of the language, and explaining the technical details o...
New
PragmaticBookshelf
Build modern server-driven web applications using htmx. Whatever programming language you use, you’ll write less (and cleaner) code. ...
New
PragmaticBookshelf
Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New
Fl4m3Ph03n1x
Background Lately I am in a quest to find a good quality TTS ai generation tool to run locally in order to create audio for some videos I...
New

Sub Categories: