How to create PySpark dataframe with schema ?

In this article, we will discuss how to create the dataframe with schema using PySpark. In simple words, the schema is the structure of a dataset or dataframe.

Functions Used:

Function	Description
SparkSession	The entry point to the Spark SQL.
SparkSession.builder()	It gives access to Builder API that we used to configure session
SparkSession.master(local)	It sets the Spark Master URL to connect to run locally.
SparkSession.appname()	Is sets the name for the application.
SparkSession.getOrCreate()	If there is no existing Spark Session then it creates a new one otherwise use the existing one.

For creating the dataframe with schema we are using:

Syntax: spark.createDataframe(data,schema)

Parameter:

• data – list of values on which dataframe is created.
• schema – It’s the structure of dataset or list of column names.

where spark is the SparkSession object.

Example 1:

• In the below code we are creating a new Spark Session object named ‘spark’.
• Then we have created the data values and stored them in the variable named ‘data’ for creating the dataframe.
• Then we have defined the schema for the dataframe and stored it in the variable named as ‘schm’. 
• Then we have created the dataframe by using createDataframe() function in which we have passed the data and the schema for the dataframe.
• As dataframe is created for visualizing we used show() function.

Python

# importing necessary libraries
from pyspark.sql import SparkSession

# function to create new SparkSession
def create_session():
  spk = SparkSession.builder \
      .master("local") \
      .appName("Geek_examples.com") \
      .getOrCreate()
  return spk

# main function
if __name__ == "__main__":

  # calling function to create SparkSession
  spark = create_session()

  #  creating data for creating dataframe
  data = [
    ("Shivansh","M",50000,2),
    ("Vaishali","F",45000,3),
    ("Karan","M",47000,2),
    ("Satyam","M",40000,4),
    ("Anupma","F",35000,5)
  ]

  # giving schema
  schm=["Name of employee","Gender","Salary","Years of experience"]

  # creating dataframe using createDataFrame()
  # function in which pass data and schema
  df = spark.createDataFrame(data,schema=schm)

  # visualizing the dataframe using show() function
  df.show()

Output:

Example 2:

In the below code we are creating the dataframe by passing data and schema in the createDataframe() function directly.

Python

# importing necessary libraries
from pyspark.sql import SparkSession

# function to create new SparkSession
def create_session():
  spk = SparkSession.builder \
      .master("local") \
      .appName("Geek_examples.com") \
      .getOrCreate()
  return spk

# main function
if __name__ == "__main__":

  # calling function to create SparkSession
  spark = create_session()

  # creating dataframe using createDataFrame()
  # function in which pass data and schema
  df = spark.createDataFrame([
    ("Mazda RX4",21,4,4),
    ("Hornet 4 Drive",22,3,2),
    ("Merc 240D",25,4,2),
    ("Lotus Europa",31,5,2),
    ("Ferrari Dino",20,5,6),
    ("Volvo 142E",22,4,2)
  ],["Car Name","mgp","gear","carb"])

  # visualizing the dataframe using show() function
  df.show()

Output: