PySpark and AWS: Master Big Data with PySpark and AWS - Total Enrollments per Course

The video tutorial explains how to count the total number of students enrolled per course using a key-value pair approach. It involves mapping course names to a value of one and then applying a reduce by key function to aggregate these values. The process is demonstrated using an IDE, where the key-value pairs are created and reduced to find the total enrollments. The tutorial provides a detailed explanation of the reduce by key process and concludes with final steps and remarks.

What is the initial step in counting student enrollments per course?

• Calculating averages

• Creating a list of courses

• Mapping course names to a value of one

• Using a database query

What does the 'reduce by key' function do after creating key-value pairs?

• It sorts the data alphabetically

• It groups and aggregates values by key

• It multiplies the values

• It deletes duplicate entries

In the context of this tutorial, what is the purpose of using a lambda function?

• To define how values are aggregated

• To delete unnecessary data

• To create a new database

• To sort the courses

What is the role of the 'map' function in this process?

• To create key-value pairs from the data

• To delete duplicate entries

• To filter out unwanted data

• To sort the data

How is the final count of enrollments determined?

• By subtracting the smallest value from the largest

• By dividing the total by the number of courses

• By summing the values for each course

• By multiplying the values

What is the significance of the 'collect' function in this process?

• To create a backup of the data

• To sort the data

• To delete temporary data

• To display the final results

What does the final output of the reduce by key function represent?

• The average number of enrollments

• The total number of enrollments per course

• The list of all courses

• The maximum enrollment in a single course