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SQL Server SUM in subquery causing arithmetic overflow when the SUM is less than a 32-bit int

The top branch of the execution plan selects all 1,098,300 rows from Inventory and performs SELECT SUM(NetWeight), ManifestID FROM Inventory GROUP BY ManifestID The output of this (estimated ...
Martin Smith's user avatar
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Finalize GroupAggregate parent using Partial HashAggregate child nodes in Postgres query plan

As the other answer explains, the individual child workers have duplicates between them. The parent needs to remove these duplicates. Both hashing and sorting are valid methods to remove duplicates. ...
ahron's user avatar
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1 vote

Finalize GroupAggregate parent using Partial HashAggregate child nodes in Postgres query plan

The parallel subplans can potentially return duplicates (in relation to the group key): since the blocks coming out of the Parallel Seq Scan are not distributed between the parallel workers by the ...
mustaccio's user avatar
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