sortBy

Returns DataFrame with rows sorted by one or several columns.

API reference: sortBy

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

Related operations: Reorder rows

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() }

sortByDesc

Returns DataFrame sorted by one or several columns in descending order.

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

df.sortByDesc { age and weight }

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

Sorting within groups

On a GroupBy, sortBy and sortByDesc sort rows only within each group.

If a referenced column cannot be found in a group, both functions throw an exception.

To sort the groups themselves by their keys, use sortByKey() or sortByKeyDesc() instead. See GroupBy transformations for other operations that reorder groups.

sortWith

Returns DataFrame sorted with comparator.

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

If called on a DataColumn, sortWith() returns the sorted version of the current column based on the given comparator.

02 November 2026