if null replace with 0, otherwise default value in same column

Question

In SparkR shell 1.5.0, Created a sample data set:

df_test <- createDataFrame(sqlContext, data.frame(mon = c(1,2,3,4,5), year = c(2011,2012,2013,2014,2015)))
d         


        

Answer 1

I have used raw SQL case when expression to get the answer,

df_test3 <- sql(sqlContext, "select mon1, mon, case when year is null then 0 else year end year FROM temp")

showDF(df_test3)
+----+----+------+
|mon1| mon|  year|
+----+----+------+
| 7.0|null|   0.0|
| 1.0| 1.0|2011.0|
| 6.0|null|   0.0|
| 3.0| 3.0|2013.0|
| 5.0| 5.0|2015.0|
| 8.0|null|   0.0|
| 4.0| 4.0|2014.0|
| 2.0| 2.0|2012.0|
+----+----+------+

Even though it gives the answer, i am looking for pure sparkR code.

Answer 2

df_test2$year <- ifelse(isNull(df_test2$year), 0, df_test2$year)

Pure SparkR code that resolves the problem.