sumBy
sumBy returns the total sum for each group. Null values are ignored.
Applying this aggregation to a column where the sum cannot be computed will result in an error. For example, the sum is not defined for a column of string values.
Syntax
table.sumBy()
table.sumBy(groupByColumns...)
Parameters
| Parameter | Type | Description |
|---|---|---|
| groupByColumns | String... | The column(s) by which to group data.
|
| groupByColumns | ColumnName... | The column(s) by which to group data.
|
| groupByColumns | Collection<String> | The column(s) by which to group data.
|
Returns
A new table containing the sum for each group.
Examples
In this example, sumBy returns the sum of the whole table. Because a sum cannot be computed for the string column X and Y, these columns are dropped before applying sumBy.
source = newTable(
stringCol("X", "A", "B", "A", "C", "B", "A", "B", "B", "C"),
stringCol("Y", "M", "N", "O", "N", "P", "M", "O", "P", "M"),
intCol("Number", 55, 76, 20, 130, 230, 50, 73, 137, 214),
)
result = source.dropColumns("X", "Y").sumBy()
- source
- result
In this example, sumBy returns the sum, as grouped by X. Because a sum cannot be computed for the string column Y, this column is dropped before applying sumBy.
source = newTable(
stringCol("X", "A", "B", "A", "C", "B", "A", "B", "B", "C"),
stringCol("Y", "M", "N", "O", "N", "P", "M", "O", "P", "M"),
intCol("Number", 55, 76, 20, 130, 230, 50, 73, 137, 214),
)
result = source.dropColumns("Y").sumBy("X")
- source
- result
In this example, sumBy returns the sum, as grouped by X and Y.
source = newTable(
stringCol("X", "A", "B", "A", "C", "B", "A", "B", "B", "C"),
stringCol("Y", "M", "N", "O", "N", "P", "M", "O", "P", "M"),
intCol("Number", 55, 76, 20, 130, 230, 50, 73, 137, 214),
)
result = source.sumBy("X", "Y")
- source
- result