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[14.0] fix: aggregation empty row on join with grouping and aggregations#10554

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deepthi merged 1 commit intovitessio:release-14.0from
planetscale:bp-10480
Jun 21, 2022
Merged

[14.0] fix: aggregation empty row on join with grouping and aggregations#10554
deepthi merged 1 commit intovitessio:release-14.0from
planetscale:bp-10480

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@harshit-gangal harshit-gangal commented Jun 21, 2022

Description

Backport of #10480

This PR fixes an aggregation-grouping bug in gen4 that does non-scalar aggregates on a top of a join.
This happens when the left side of the join has data and no data is present on the right hand side.
If the right hand side of the join only contains an aggregation then even though the table has no data it will return count(*) as 0 and that will get mapped to the join output.
To avoid such scenario the change adds a grouping condition on the right hand side using literal 1 so that the rows from right hand side is only returned when the join condition matches.

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@harshit-gangal
fix: aggregation empty row on join with grouping and aggregations (vi…
46ca748 
…tessio#10480)

Signed-off-by: Harshit Gangal <harshit@planetscale.com>
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github-actions bot commented Jun 21, 2022

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deepthi commented Jun 21, 2022

Not sure why DCO is stalled. I've manually verified that the commit has been signed off.

@deepthi deepthi merged commit 47eec73 into vitessio:release-14.0 Jun 21, 2022
@deepthi deepthi deleted the bp-10480 branch June 21, 2022 19:20
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@systay systay systay approved these changes

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