How to select and order multiple columns in Pyspark DataFrame ?

In this article, we will discuss how to select and order multiple columns from a dataframe using pyspark in Python. For this, we are using sort() and orderBy() functions along with select() function.

Methods Used

• Select(): This method is used to select the part of dataframe columns and return a copy of that newly selected dataframe.

Syntax: dataframe.select([‘column1′,’column2′,’column n’].show()

• sort(): This method is used to sort the data of the dataframe and return a copy of that newly sorted dataframe. This sorts the dataframe in ascending by default.

Syntax: dataframe.sort([‘column1′,’column2′,’column n’], ascending=True).show()

• oderBy(): This method is similar to sort which is also used to sort the dataframe.This sorts the dataframe in ascending by default.

Syntax: dataframe.orderBy([‘column1′,’column2′,’column n’], ascending=True).show()

Let’s create a sample dataframe

Python3

# importing module
import pyspark

# importing sparksession from
# pyspark.sql module
from pyspark.sql import SparkSession

# creating sparksession and giving an app name
spark = SparkSession.builder.appName('sparkdf').getOrCreate()

# list  of students  data
data = [["1", "sravan", "vignan"], ["2", "ojaswi", "vvit"],
        ["3", "rohith", "vvit"], ["4", "sridevi", "vignan"],
        ["1", "sravan", "vignan"], ["5", "gnanesh", "iit"]]

# specify column names
columns = ['student ID', 'student NAME', 'college']

# creating a dataframe from the lists of data
dataframe = spark.createDataFrame(data, columns)

print("Actual data in dataframe")
# show dataframe
dataframe.show()

Output:

Selecting multiple columns and order by using sort() method

Python3

# show dataframe by sorting the dataframe
# based on two columns in ascending
# order using sort() function
dataframe.select(['student ID', 'student NAME']
                ).sort(['student ID', 'student NAME'],
                       ascending=True).show()

Output:

Python3

# show dataframe by sorting the dataframe
# based on three columns in desc order
# using sort() function
dataframe.select(['student ID', 'student NAME', 'college']
                ).sort(['student ID', 'student NAME', 'college'],
                       ascending=False).show()

Output:

Selecting multiple columns and order by using orderBy() method

Python3

# show dataframe by sorting the dataframe
# based on three columns in desc
# order using orderBy() function
dataframe.select(['student ID', 'student NAME', 'college']
                ).orderBy(['student ID', 'student NAME', 'college'],
                          ascending=False).show()

Output:

Python3

# show dataframe by sorting the dataframe
# based on two columns in asc
# order using orderBy() function
dataframe.select(['student NAME', 'college']
                ).orderBy(['student NAME', 'college'],
                          ascending=True).show()

Output: