Dividing complex rows of dataframe to simple rows in Pyspark

user_5970714 0
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I have this code:

from pyspark import SparkContext
from pyspark.sql import SQLContext, Row

sc = SparkContext()
sqlContext = SQLContext(sc)
documents = sqlContext.createDataFrame([
    Row(id=1, title=[Row(value=u'cars', max_dist=1000)]),
    Row(id=2, title=[Row(value=u'horse bus',max_dist=50), Row(value=u'normal bus',max_dist=100)]),
    Row(id=3, title=[Row(value=u'Airplane', max_dist=5000)]),
    Row(id=4, title=[Row(value=u'Bicycles', max_dist=20),Row(value=u'Motorbikes', max_dist=80)]),
    Row(id=5, title=[Row(value=u'Trams', max_dist=15)])])

documents.show(truncate=False)
#+---+----------------------------------+
#|id |title                             |
#+---+----------------------------------+
#|1  |[[1000,cars]]                     |
#|2  |[[50,horse bus], [100,normal bus]]|
#|3  |[[5000,Airplane]]                 |
#|4  |[[20,Bicycles], [80,Motorbikes]]  |
#|5  |[[15,Trams]]                      |
#+---+----------------------------------+

I need to split all compound rows (e.g. 2 & 4) to multiple rows while retaining the 'id', to get a result like this:

#+---+----------------------------------+
#|id |title                             |
#+---+----------------------------------+
#|1  |[1000,cars]                       |
#|2  |[50,horse bus]                    |
#|2  |[100,normal bus]                  |
#|3  |[5000,Airplane]                   |
#|4  |[20,Bicycles]                     |
#|4  |[80,Motorbikes]                   |
#|5  |[15,Trams]                        |
#+---+----------------------------------+
pyspark apache-spark-sql apache-spark dataframe python
3 Answers

I am using Spark Dataset API, and following solved the 'explode' requirement for me:

Dataset<Row> explodedDataset = initialDataset.selectExpr("ID","explode(finished_chunk) as chunks");

Note: The explode method of Dataset API is deprecated in Spark 2.4.5 and the documentation suggests using Select(shown above) or FlatMap.

user_28179080
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