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Percentiles for sure are better than average if you want to explore distribution: there are several percentiles comparing to single average. However median is harder to use if you want to do calculations based on this metric. For example distribution of sample median could be a problem, if you want to understand confidence interval for it for example.

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NB: Post author here.

Totally can be true. In our case, we use these approximation methods that allow you to get multiple percentiles "for free" definitely need to choose the right ones for the job. (We talk a bit more about the whole approach where we do the aggregation then the accessor thing in the previous post on two-step aggregation [1]). But there are definitely times when averages/stddev and potentially the 3rd and 4th moments are more useful etc.

[1]: https://blog.timescale.com/blog/how-postgresql-aggregation-w...

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