union replaces unionAll

The dataset and DataFrame API unionAll has been deprecated and replaced by union.

Type of change: Syntactic/Spark core change

Spark 1.6

unionAll is supported.

Spark 2.4

unionAll is deprecated and replaced by union.

Action Required

Replace unionAll with union. For example:val df3 = df.unionAll(df2) with val df3 = df.union(df2)