Replacing groupBykey() with reduceByKey()

Asked Aug 03 '18 at 20:56

Active Aug 03 '18 at 22:00

Viewed 45 times

I am trying to replace groupByKey() with reudceByKey(), I am a pyspark and python newbie and I am having a hard time figuring out the lambda function for the reduceByKey() operation.

Here is the code

dd = hive_context.read.orc(orcfile_dir).rdd.map(lambda x: (x[0],x)).groupByKey(25).take(2)

Here is the return value

>>> dd
[(u'KEY_1', <pyspark.resultiterable.ResultIterable object at 0x107be0c50>), (u'KEY_2', <pyspark.resultiterable.ResultIterable object at 0x107be0c10>)]

and Here are the iterable contents dd[0][1]

Row(key=u'KEY_1', hash_fn=u'deec95d65ca6b3b4f2e1ef259040aa79', value=u'e7dc1f2a')
Row(key=u'KEY_1', hash_fn=u'f8891048a9ef8331227b4af080ecd28a', value=u'fb0bc953')
....
...
Row(key=u'KEY_1', hash_fn=u'1b9d2bb2db28603ff21052efcd13f242', value=u'd39714d3')
Row(key=u'KEY_1', hash_fn=u'c41b0269706ac423732a6bab24bf8a6a', value=u'ab58db92')

My question is how do replace with reduceByKey() and get the same output as above?

edited Aug 03 '18 at 22:00

asked Aug 03 '18 at 20:56

Santhosh

is your first replaceByKey meant to be reduceByKey? – joel Aug 03 '18 at 21:09
@JoelBerkeley thanks for pointing it out. yes it's a typo. Fixing it now – Santhosh Aug 03 '18 at 21:28

Replacing groupBykey() with reduceByKey()

0 Answers0