Markus Winand
Markus Winand writes about SQL indexing, query performance and modern SQL features for application developers.
What HN says
Commenters recommend it highly as a readable guide to database indexing, and some say they have new hires and interns read it.
Stats for nerds
171HN people shared it
137linked in comments
1.7Kstory points
Jun 2026last shared
Top posts on HN
- 1MongoDB is to NoSQL like MySQL to SQL - in the most harmful way3 people · 224 points · first shared 2013 · 124 comments on HN
- 2SQL Indexing and Tuning E-Book for Developers86 people · 206 points · first shared 2010 · 6 comments on HN
- 3Results of the SQL Performance Quiz2 people · 179 points · first shared 2014 · 93 comments on HN
- 4On Uber’s Choice of Databases9 people · 169 points · first shared 2016 · 13 comments on HN
- 5What's left of NoSQL?4 people · 148 points · first shared 2014 · 104 comments on HN
- 6SQL Indexing and Tuning e-Book1 person · 130 points · first shared 2012 · 11 comments on HN
- 7The 3-minute SQL indexing quiz: Can you spot the five most common mistakes?3 people · 111 points · first shared 2011 · 32 comments on HN
- 8Big News in Databases1 person · 95 points · first shared 2016 · 23 comments on HN
- 9Myth: Select * is Bad1 person · 87 points · first shared 2013 · 67 comments on HN
- 10Everybody thinks SQL joins are slow-is it because MySQL doesn't have hash joins?2 people · 41 points · first shared 2011 · 24 comments on HN
What HN people wrote when they linked it
- j_sOct 2017
Here's a recent discussion recommending a specific site that might help you as a resource, but I don't see much there regarding locality.
How far can you go with MySQL or MariaDB?
| https://news.ycombinator.com/item?id=14892184 (Aug 2017)> dmux This is a great resource RE indexing: http://use-the-index-luke.com/
There is a detailed PostgreSQL optimization comment there that may be more what you had in mind:
https://news.ycombinator.com/item?id=14896154
> olavgg: Use multi-column/functional/partial indexes, as this will help you design a database where most of your 'hot' indexes can fit in RAM. If you have too many indexes, you will do index scan on disk, which is painfully slow. I[n] many cases a full table scan (sequential read) would be faster instead.
- twoquestionsJul 2021
To learn yourself, also go over the execution plan when running a query and Google absolutely everything it tells you, and look through the MSSQL documentation at what it all means. It won't lead you to what you don't know, but it will fill in everything you're a bit cloudy on.
One of my favorites to get the very basics is Select Star, especially because you work with real and meaningful data: https://selectstarsql.com/
Use the Index, Luke has also really helped me make queries that don't waste a ton of time:
https://use-the-index-luke.com/Microsoft also has a bunch of paid training classes for MSSQL, if you or your boss don't mind ponying up some $$$. MSSQL is an amazing tool, and it's worth it to really learn how to use it well.
Good luck!
- moreaccountsplsJul 2020
There's a difference between operating the database [SRE type job] vs consuming a database [developer]. They're both very valuable skills, but learning the basics of SQL [i.e. being a consumer] is a no brainer. The skills will serve you well for the rest of your career. It's not something that changes every few years like frontend frameworks do.
This is my favorite learning material for ANY programming related skill ever: https://use-the-index-luke.com/, and it's all about SQL queries.
- dguaragliaAug 2016
If what you are looking is a general book (not necessarily just for Postgres) I can't recommend the "Use The Index, Luke"[1] tutorial, and the accompanying book "SQL Performance Explained" by Markus Winand, enough.
It doesn't go into a lot of relational theory, but it does provide a somewhat low-level description on how indices and database data are stored, and why you want to use different kind of indices in different scenarios.
[1] http://use-the-index-luke.com
- aleccoSep 2020
For practical knowledge start with databases. Declarative is a great way to program, and a good starting point is https://use-the-index-luke.com/
About CompSci, it might get a bit dry at times. Seduce yourself into it, watch some Computerphile YouTube videos instead of a textbook. Then when you get the interest bug, search for what you are interested in. Try to keep it fun.
Once you built stamina, TAOC and SICP.
https://web.mit.edu/alexmv/6.037/sicp.pdf
- tdfirthDec 2025
If you do backend web development in 99% of software companies then being very good at whatever your RDBMS is is a superpower.
It's definitely worth learning SQL very well, but you also need to learn the data structures your RDBMS uses, how queries translate into operations on that data, and what those operations look like in a query plan.
You can go surprisingly far with just that knowledge.
A great resource is https://use-the-index-luke.com/