Based on: https://web.mit.edu/databases/mysql/mysql-3.23.6-alpha/Docs/manual.html#Multiple-column_indexes https://web.mit.edu/databases/mysql/mysql-3.23.6-alpha

Based on: https://web.mit.edu/databases/mysql/mysql-3.23.6-alpha/Docs/manual.html#Multiple-column_indexes https://web.mit.edu/databases/mysql/mysql-3.23.6-alpha/Docs/... I'd say there's very little performance gain in normalizing (it usually goes the other way anyway: normalize for good design, avoiding storing multiple copies of individual columns; de-normalize for performance). I'm a little surprised by the tone of the article - sure, there were universities that taught computer science without a database course - but it's not like there weren't practical books on dB design in the 90s and onward? I guess it's meant as a critique of the mentioned, but not linked other article "being discussed in the usual places".