The given Dataframe 'rating' has repeated rows. You need to remove the duplicated rows. code example
Example: Return a new DataFrame with duplicate rows removed
# Return a new DataFrame with duplicate rows removed
from pyspark.sql import Row
df = sc.parallelize([
Row(name='Alice', age=5, height=80),
Row(name='Alice', age=5, height=80),
Row(name='Alice', age=10, height=80)]).toDF()
df.dropDuplicates().show()
# +---+------+-----+
# |age|height| name|
# +---+------+-----+
# | 5| 80|Alice|
# | 10| 80|Alice|
# +---+------+-----+
df.dropDuplicates(['name', 'height']).show()
# +---+------+-----+
# |age|height| name|
# +---+------+-----+
# | 5| 80|Alice|
# +---+------+-----+