a tumblelog
Tue 12 Nov 2019

Avoid OR for better PostgreSQL query performance

PostgreSQL query tuning is our daily bread at Cybertec, and once you have done some of that, you’ll start bristling whenever you see an OR in a query, because they are usually the cause for bad query performance.

Of course there is a reason why there is an OR in SQL, and if you cannot avoid it, you have to use it. But you should be aware of the performance implications.

In this article I’ll explore “good” and “bad” ORs and what you can do to avoid the latter.

Source: avoid OR for better PostgreSQL query performance, an article by Laurenz Albe.

Finding a memory leak in a Go app with cgo bindings

Usually, finding a leak in Go apps is rather trivial thanks to the built-in profiling tool that comes with Go. go tool pprof with a minimum setup steps will show you all recent allocations and the overview of the memory heap. Our case turned out to be a lot more interesting.

Source: Finding a memory leak in a Go app with cgo bindings · Kir Shatrov, an article by Kir Shatrov.

When to Use a List Comprehension in Python

Python is famous for allowing you to write code that’s elegant, easy to write, and almost as easy to read as plain English. One of the language’s most distinctive features is the list comprehension, which you can use to create powerful functionality within a single line of code. However, many developers struggle to fully leverage the more advanced features of a list comprehension in Python. Some programmers even use them too much, which can lead to code that’s less efficient and harder to read.

Source: When to Use a List Comprehension in Python, a tutorial by James Timmins.