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Introduction

Welcome to my first project using Power BI!

A month ago, I analyzed the Pizza Sales dataset from Kaggle by creating SQL quieries; you can check out that post here. However, this time, I will analyze the same dataset by creating visuals instead of queries.

Connecting the Data

Because I previously used a SQL database to analyze the pizza sales, I'm going to connect that database into a Power BI report.

So, I will click on "Get Data" on the home ribbon and click on the "PostgresSQL database" button, like so: image

Then, I put the SQL server and database name: image

After that, I got this pop-up window: image

Usually I would click on "Transform data" but because I already cleaned the data in the SQL database, I will just click on "Load".

Data Model

I don't have to make any changes in the data model. Looking at the image, this is a pretty simple project and there is only one table involved, so there isn't any relationships that need to be established: image

So, I can now dive into creating visuals for this dataset. However, before I do that, I'm going to revisit the statistical questions that I used in the SQL post:

Statistical Questions

  1. What days and times do we tend to be busiest?
  2. What are our best and worst-selling pizzas?
  3. What's our average order value?

I'm going to be showing you a visual that answers each statistical question, and after that, I will show you what my report looks like as a whole.

Statistical Question 1: What days and times do we tend to be busiest?

I need to use DAX in order to answer this question. There's a DAX function called HOUR that retrieves all the hours from timestamps. So, here's what I did.

I have a column called "order_time" that has all the timestamps of when each pizza was ordered. This is what the code looks like: image

Then, I created a simple bar chart that shows the relationship between the hour and the quantity of pizzas sold: image

Looking at the chart, the busiest time for this fictional pizza business is the 12th hour, which is noon.

I also need to show what the busiest day for the business is. To do this, we need to use more DAX!

I created a new column using the DAX function callled WEEKDAY: image

This basically returns integers from the dates in the column called "order_date". The integers range from 1 to 7 with 1 representing "Sunday" and 7 representing "Saturday". However, I want to convert these integers to the actual days of the week, so I will have to use another DAX function called IF: image

Here, I created a new column that contains the actual names of the days of the week based on the numbers from 1 to 7. image

This bar chart shows that Fridays, Saturdays, and Sundays sell the most pizzas.

Statistical Question 2: What are our best and worst-selling pizzas?

BEST SELLING PIZZAS To answer this question on Power BI, I used the "pizza_name" and "quantity" column. Because there are many values in the "pizza_name", I used a filter to only show the 5 pizzas that are sold the most. This would reduce clutter in the bar chart. image

Here's what the visual looks like: image

There doesn't seem to be much difference in the number of pizzas sold for the top 5 types. Nevertheless, based on the chart, "Classic Deluxe Pizza" seems to be the popular choice among the customers.

WORST SELLING PIZZAS I used a filter again, but this time, I filtered the bottom 5 pizzas sold. image

Here's how it looks: image

The "Brie Carre Pizza" seems to be the least popular pizza in the business with only 490 of them being sold.

Statistical Question 3: What's our average order value?

I'm going to find the average price for the pizzas based on the size. So, I'm going to use the "pizza_size" and "total_price" column to answer this question.

I made a treemap: image

Not surprisingly, the bigger the size of the pizza, the more expensive the average price is. The XXL pizza size has the most expensive average price of $35.95.

The Final Report

I played around in the Power BI Report and polished the visuals that I showed above and did my best to make it visually appealing: image

Conclusion

Thank you for reading this post! I hope you enjoyed it. If you want to see my other content related to Power BI, check out this previous post.


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