'Comparing two array columns in Scala Spark

I have a dataframe of format given below.

movieId1 | genreList1              | genreList2
--------------------------------------------------
1        |[Adventure,Comedy]       |[Adventure]
2        |[Animation,Drama,War]    |[War,Drama]
3        |[Adventure,Drama]        |[Drama,War]

and trying to create another flag column which shows whether genreList2 is a subset of genreList1

movieId1 | genreList1              | genreList2        | Flag
---------------------------------------------------------------
1        |[Adventure,Comedy]       | [Adventure]       |1
2        |[Animation,Drama,War]    | [War,Drama]       |1
3        |[Adventure,Drama]        | [Drama,War]       |0

I have tried this

def intersect_check(a: Array[String], b: Array[String]): Int = {
  if (b.sameElements(a.intersect(b))) { return 1 } 
  else { return 2 }
}

def intersect_check_udf =
  udf((colvalue1: Array[String], colvalue2: Array[String]) => intersect_check(colvalue1, colvalue2))

data = data.withColumn("Flag", intersect_check_udf(col("genreList1"), col("genreList2")))

But this throws org.apache.spark.SparkException: Failed to execute user defined function. Error. Any ideas on how to resolve this. P.S.: The above function (intersect_check) works for Arrays.

Solution 1:^[1]

Here is the solution converting using subsetOf

  val spark =
    SparkSession.builder().master("local").appName("test").getOrCreate()

  import spark.implicits._

  val data = spark.sparkContext.parallelize(
  Seq(
    (1,Array("Adventure","Comedy"),Array("Adventure")),
  (2,Array("Animation","Drama","War"),Array("War","Drama")),
  (3,Array("Adventure","Drama"),Array("Drama","War"))
  )).toDF("movieId1", "genreList1", "genreList2")


  val subsetOf = udf((col1: Seq[String], col2: Seq[String]) => {
    if (col2.toSet.subsetOf(col1.toSet)) 1 else 0
  })

  data.withColumn("flag", subsetOf(data("genreList1"), data("genreList2"))).show()

Hope this helps!

Solution 2:^[2]

One solution may be to exploit spark array builtin functions: genreList2 is subset of genreList1 if the intersection between the two is equal to genreList2. In the code below a sort_array operation has been added to avoid a mismatch between two arrays with different ordering but same elements.

val spark = {
    SparkSession
    .builder()
    .master("local")
    .appName("test")
    .getOrCreate()
}

import spark.implicits._
import org.apache.spark.sql._
import org.apache.spark.sql.functions._

val df = Seq(
    (1, Array("Adventure","Comedy"), Array("Adventure")),
    (2, Array("Animation","Drama","War"), Array("War","Drama")),
    (3, Array("Adventure","Drama"), Array("Drama","War"))
).toDF("movieId1", "genreList1", "genreList2")

df
.withColumn("flag",
 sort_array(array_intersect($"genreList1",$"genreList2"))
 .equalTo(
   sort_array($"genreList2")
 )
.cast("integer")
)
.show()

The output is

+--------+--------------------+------------+----+
|movieId1|          genreList1|  genreList2|flag|
+--------+--------------------+------------+----+
|       1| [Adventure, Comedy]| [Adventure]|   1|
|       2|[Animation, Drama...|[War, Drama]|   1|
|       3|  [Adventure, Drama]|[Drama, War]|   0|
+--------+--------------------+------------+----+

Solution 3:^[3]

This can also work here and it does not use udf

 import spark.implicits._
 val data = Seq(
        (1,Array("Adventure","Comedy"),Array("Adventure")),
        (2,Array("Animation","Drama","War"),Array("War","Drama")),
        (3,Array("Adventure","Drama"),Array("Drama","War"))
      ).toDF("movieId1", "genreList1", "genreList2")

 data
     .withColumn("size",size(array_except($"genreList2",$"genreList1")))
     .withColumn("flag",when($"size" === lit(0), 1) otherwise(0))
     .show(false)

Sources

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Source: Stack Overflow

Solution	Source
Solution 1	koiralo
Solution 2
Solution 3	whoisthis

'Comparing two array columns in Scala Spark

Solution 1:[1]

Solution 2:[2]

Solution 3:[3]

Sources

Related Questions

Solution 1:^[1]

Solution 2:^[2]

Solution 3:^[3]