sortBy

Returns DataFrame with rows sorted by one or several columns.

By default, columns are sorted in ascending order with null values going first. Available modifiers:

• .desc — changes column sort order from ascending to descending

• .nullsLast — forces null values to be placed at the end of the order

See column selectors for how to select the columns for this operation.

df.sortBy { age }
df.sortBy { age and name.firstName.desc() }
df.sortBy { weight.nullsLast() }

df.sortBy("age")
df.sortBy { "age" and "name"["firstName"].desc() }
df.sortBy { "weight".nullsLast() }

df.sortByDesc { age and weight }

df.sortByDesc("age", "weight")

df.sortWith { row1, row2 ->
    when {
        row1.age < row2.age -> -1
        row1.age > row2.age -> 1
        else -> row1.name.firstName.compareTo(row2.name.firstName)
    }
}