How to make your code 500x faster*

June 5, 2017 ~ Bob ~ 4 Comments

(*Sorry, the techniques I describe don't apply in all circumstances.) This graph shows the time taken by 8 different ways of doing exactly the same thing: retrieving the details of 20,000 orders from a database. The taller the bar, the more time it took. Unfortunately I had to use a log scale because the range … Continue reading How to make your code 500x faster*

Make your test data more vicious

June 2, 2017 ~ Bob ~ 1 Comment

Imagine you have some code that works with data from a table that stores customer orders. Unfortunately your code has a bug - instead of using CustomerId for something it uses OrderId instead (both are fields on the table). What's worse, your tests pass and the test coverage looks fine. What's up? I'll assume that … Continue reading Make your test data more vicious