Mat views are great as the article showed. I use them to get query response down to milliseconds, as they vastly reduce the amount of data ClickHouse must scan.
That said, there are a lot of other tools: column storage, vectorwise query, efficient compression including column codecs, and skip indexes to name a few. If you only have a few billion rows it's still possible to get sub-second query results using brute force scans.
Disclaimer: I work for Altinity, who wrote this article.
p.s. Loading the view is low-cost compared to loading the source data. On the NUC it's 40-60 minutes, so worst case it's something like 1h / 17.5h = 5.71%. Also, you can still query the source data. That is fast for individual sensors as the examples showed.
That said, there are a lot of other tools: column storage, vectorwise query, efficient compression including column codecs, and skip indexes to name a few. If you only have a few billion rows it's still possible to get sub-second query results using brute force scans.
Disclaimer: I work for Altinity, who wrote this article.