Converting yyyymmdd to MM-dd-yyyy format in pyspar

问题:

I have a large data frame df containing a column for date in the format yyyymmdd, how can I convert it into MM-dd-yyyy in pySpark.

回答1:

from datetime import datetime
from pyspark.sql.functions import col,udf
from pyspark.sql.types import DateType


rdd = sc.parallelize(['20161231', '20140102', '20151201', '20161124'])
df1 = sqlContext.createDataFrame(rdd, ['old_col'])

//UDF to convert string to date
func =  udf (lambda x: datetime.strptime(x, '%Y%M%d'), DateType())

df = df1.withColumn('new_col', date_format(func(col('old_col')), 'MM-dd-yyy'))

df.show()

回答2:

This is also working:

from datetime import datetime
from pyspark.sql.functions import col,udf,unix_timestamp
from pyspark.sql.types import DateType


func =  udf(lambda x: datetime.strptime(str(x), '%m%d%y'), DateType())

df2 = df.withColumn('date', func(col('InvcDate')))