Module datafusion::physical_plan::aggregates
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Aggregates functionalities
Structs
Hash aggregate execution plan
Represents GROUP BY
clause in the plan (including the more general GROUPING SET)
In the case of a simple GROUP BY a, b
clause, this will contain the expression [a, b]
and a single group [false, false].
In the case of GROUP BY GROUPING SET/CUBE/ROLLUP
the planner will expand the expression
into multiple groups, using null expressions to align each group.
For example, with a group by clause GROUP BY GROUPING SET ((a,b),(a),(b))
the planner should
create a PhysicalGroupBy
like
PhysicalGroupBy {
expr: [(col(a), a), (col(b), b)],
null_expr: [(NULL, a), (NULL, b)],
groups: [
[false, false], // (a,b)
[false, true], // (a) <=> (a, NULL)
[true, false] // (b) <=> (NULL, b)
]
}
Enums
Enum of all built-in aggregate functions
Hash aggregate modes
Functions
Create a physical aggregation expression.
This function errors when input_phy_exprs
’ can’t be coerced to a valid argument type of the aggregation function.