Preserve order for root for SINGLE distribution only#14871
Merged
losipiuk merged 1 commit intotrinodb:masterfrom Nov 3, 2022
Merged
Preserve order for root for SINGLE distribution only#14871losipiuk merged 1 commit intotrinodb:masterfrom
losipiuk merged 1 commit intotrinodb:masterfrom
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We need to set preserveOrderWithinPartition flag only if root stage of plan requires total ordering. The need of total ordering implies that SINGLE distribution will be used for root stage. Note there still can be cases when SINGLE distribution is used but we do not really need to preserve order. Improving on that is a followup work as it requires annotating plan with information if output ordering is required or not.
arhimondr
approved these changes
Nov 2, 2022
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We need to set preserveOrderWithinPartition flag only if root stage of plan requires total ordering. The need of total ordering implies that SINGLE distribution will be used for root stage.
Note there still can be cases when SINGLE distribution is used but we do not really need to preserve order. Improving on that is a followup work as it requires annotating plan with information if output ordering is required or not.
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