Data Visualisation & Analytics
When you build dynamic websites, you will eventually collect data, and visualising analysing that data becomes a challenge in itself.
Most of my websites record data in MySQL, so I have lots of experience writing queries to aggregate data. Often those queries need optimising because you are generally aggregating lots of data.
Website analytics have also become huge in the last decade, so inevitably I have become well versed with using Google Analytics, Tag Manager, and Data Studio.
Here are some of the projects I have build that have some reports/charts/data aggregation: