How to replace item in array with other values in spark?

Question

+--------------------------------+
|Subject                         |
+--------------------------------+
|[English, Math, Science, Spark] |
+--------------------------------+
|[English, History, Art]         |
+--------------------------------+

How can we replace English with ENGLISH in both rows?

Answer 1

Use a custom UDF to replace the word:

val replace = udf{ x: Seq[String] => x.map(y => if(y == "English") "ENGLISH" else y) }

val df2 = df.select(replace($"Subject").alias("Subject"))

df2.show(false)
+-------------------------------+
|Subject                        |
+-------------------------------+
|[ENGLISH, Math, Science, Spark]|
|[ENGLISH, History, Art]        |
+-------------------------------+