Data Origin
The Data for Udemy Project has been extracted from Kaggle Datasets. The data contains information about whole financial courses in Udemy and consists about course reviews, subscribers, price and so on. We are going to make some insights from the data after cleaning it with Microsoft SQL Server. The link to the dataset is here.
Data Cleaning
The Data cleaning is done using Microsoft SQL Server. The code is also posted in GitHub : https://github.com/smzahir/Portfolio-Project
-- Exploratory Data Analysis Of Udemy Financial Courses
SELECT *
FROM Udemy_data
-- Removing unwanted columns from the table
ALTER TABLE Udemy_data
DROP COLUMN url, avg_rating, avg_rating_recent, is_wishlisted,
num_published_practice_tests, created, discount_price__currency,
discount_price__price_string, price_detail__price_string,
price_detail__currency
-- Renaming columns for better understanding
sp_rename 'Udemy_data.id','ID'
GO
sp_rename 'Udemy_data.title','Title'
GO
sp_rename 'Udemy_data.is_paid','PaidCourse'
GO
sp_rename 'Udemy_data.num_subscribers','Subscribers'
GO
sp_rename 'Udemy_data.rating','Rating'
GO
sp_rename 'Udemy_data.num_reviews','Reviews'
GO
sp_rename 'Udemy_data.num_published_lectures','LecturesPublished'
GO
sp_rename 'Udemy_data.published_time','DatePublished'
GO
sp_rename 'Udemy_data.discount_price__amount','OfferPrice'
GO
sp_rename 'Udemy_data.price_detail__amount','Price'
-- As checked OfferPrice and Price Columns contains null values
SELECT *
FROM Udemy_data
WHERE Price IS NULL
-- Replacing null values with Zeroes
UPDATE Udemy_data
SET Price =
CASE
WHEN Price IS NULL THEN 0
ELSE Price
END
UPDATE Udemy_data
SET OfferPrice =
CASE
WHEN OfferPrice IS NULL THEN 0
ELSE OfferPrice
END
-- Converting DataPublished into Date type only
UPDATE Udemy_data
SET DatePublished =
CAST(DatePublished AS DATE)