Proposal: Getting rid of Neighbors in Path Queries#6125
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neilkakkar merged 5 commits intomasterfrom Sep 29, 2021
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neilkakkar
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Sep 27, 2021
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I very much dislike
neighborsfunction because: https://clickhouse.com/docs/en/sql-reference/functions/other-functions/#neighborI'm proposing leveraging arrays to get the same job done. It uses a bit more memory than before (one more copy of the array for each person) - but gets rid of global sorting.
Another improvement this query makes: Ensures the
groupArrayworks correctly.From the docs:
Values can be added to the array in any (indeterminate) order.To fix this, you order by the correct things in a subquery.We're already ordering by timestamp in
PathEventQuery, so don't need to order by personID in the outer clause.Checklist