Metadata, not data, is what drags your database down

In recent years, data has seen exponential growth due to evolving connected devices and the Internet of Things (IoT). With this comes an alarming rate of expansion in the amount of metadata, meaning data that describes and provides information on other data. Although metadata has always been around, it used to be stored in memory and behind the scenes, as it came at a fraction of the size it is today.

Adi Gelvan
The Stack Flow