headBy
headBy returns the first n rows for each group.
Syntax
Parameters
| Parameter | Type | Description |
|---|---|---|
| nRows | long | The number of rows to return for each group. |
| groupByColumnNames | String... | The column(s) by which to group data.
|
| groupByColumnNames | Collection<String> | The column(s) by which to group data.
|
Returns
A new table containing the first n rows for each group.
Examples
In this example, headBy returns the first 2 rows, as grouped by X.
In this example, headBy returns the first 2 rows, as grouped by X and Y.