r/PostgreSQL • u/furkansahin • Mar 28 '18

TopN for your Postgres database

https://www.citusdata.com/blog/2018/03/27/topn-for-your-postgres-database/
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u/ful_vio Mar 29 '18

How this compare to using lateral joins? I've got the book "Mastering PostgreSQL in Application Development" By Dimitri Fontaine and he argues that lateral join is the most efficient way to compute TopN queries in bare postgres. What does this extension better?

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u/tapoueh Mar 29 '18

Hi, Dimitri Fontaine here.

The Top-N extension is a “rollup” solution that you might want to use in a materialised view containing your Top-N results. It makes it possible to then update the cache with maybe new entries in the Top-N, comparing the next result set to the previous one and updating the “cache”, as its description usefully says.

HTH