Example: Grouping data in a simple way

Example where people table is grouped by last name.

df.groupBy("surname").count().show()

+-------+-----+
|surname|count|
+-------+-----+
| Martin|    1|
| Garcia|    3|
+-------+-----+

Example: pooling data combined with filter

Example where the people table is grouped by surname and the ones with more than 2 appearances are Selected.

df.groupBy("surname").count().filter("count > 2").show()

+-------+-----+
|surname|count|
+-------+-----+
| Garcia|   3 |
+-------+-----+