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- If tree evaluation returned empty partition set, return empty result set immediately without actual query execution
- If tree evaluation returned one partition, then all data reside on a single node. Convert query to "local" and execute it on target node without two-phase flow
- If tree evaluation returned several partitions, and all of them appear to be on the same node, then try to execute query speculatively on a single node, provided that partitions are still on that node. Fallback to normal execution mode in case of concurrent eviction.
Management and Monitoring
It is very important to let user know if partition pruning is applicable to query for performance tuning. For every cached two-step query we may expose the following information:
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