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Optimize DISTINCT + ORDER BY
See original GitHub issueFollowing Slack discussion : https://apache-pinot.slack.com/archives/C011C9JHN7R/p1623782718117700
Context Documents: 100M Segments: 90
Query Getting DISTINCT values for a low cardinality column (45 distinct STRINGs)
Query select DISTINCT(kpi) from kpis takes ~10ms
While select DISTINCT(kpi) from kpis ORDER BY kpi takes more than 300ms
Please have a look at the discussion by @mayankshriv and @kishoreg for more technical details
Issue Analytics
- State:
- Created 2 years ago
- Comments:13 (10 by maintainers)
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I would say that we document this behaviour and make users aware of this scenario. WDYT?
Since we have agreement, marking the issue as closed.