Error: not found: value lit/when - spark scala - scala

Question

I am using scala, spark, IntelliJ and maven.
I have used below code :
val joinCondition = when($"exp.fnal_expr_dt" >= $"exp.nonfnal_expr_dt",
$"exp.manr_cd"===$"score.MANR_CD")
val score = exprDF.as("exp").join(scoreDF.as("score"),joinCondition,"inner")
and
val score= list.withColumn("scr", lit(0))
But when try to build using maven, getting below errors -
error: not found: value when
and
error: not found: value lit
For $ and === I have used import sqlContext.implicits.StringToColumn and it is working fine. No error occurred at the time of maven build.But for lit(0) and when what I need to import or is there any other way resolve the issue.

Answer 1

Let's consider the following context :
val spark : SparkSession = _ // or val sqlContext: SQLContext = new SQLContext(sc) for 1.x
val list: DataFrame = ???
To use when and lit, you'll need to import the proper functions :
import org.apache.spark.sql.functions.{col, lit, when}
Now you can use them as followed :
list.select(when(col("column_name").isNotNull, lit(1)))
Now you can use lit also in your code :
val score = list.withColumn("scr", lit(0))