将字符串日期（不带分隔符）转换为 Scala 中的日期格式

Question

i have some issues to convert a column with Dates. my date column Looks like this "20032016" "ddMMyyyy". When i convert it, i get only null. I used following code:

df.withColumn("reporting_date",date_format(to_date(col("reporting_date"), "ddMMyyyy"), "yyyy-MM-dd")).show 

does someone can help me?

Answer 1

Your code example works for me:

scala> val df = Seq("20032016").toDF
df: org.apache.spark.sql.DataFrame = [value: string]

scala> df.withColumn("reporting_date",date_format(to_date(col("value"), "ddMMyyyy"), "yyyy-MM-dd")).show
+--------+--------------+
|   value|reporting_date|
+--------+--------------+
|20032016|    2016-03-20|
+--------+--------------+