Part 2: Data Analysis with powerful Python – How to get the best results from your data

Analyzing and visualizing data from a SQLite database in Python can be a powerful way to gain insights and present your findings. In this blog, I will walk you through the steps to retrieve data from a SQLite database file named gold.db and display it in the form of a chart using Python. We'll use some essential tools and libraries for this task.

Tools you will need !

Before we start, make sure you have the following tools and libraries installed:

1. Python: Python is the core programming language for this task. You can download it from python.org.

2. SQLite Database Browser: You can use a tool like DB Browser for SQLite to explore the database and its structure. This is optional but can be helpful for understanding the database schema.

3. Jupyter Notebook (optional): Jupyter Notebook is an interactive environment that makes data analysis and visualization easier. You can install it using pip: pip install jupyter.

4. Python Libraries:

   • sqlite3: This is a built-in library for Python that allows you to work with SQLite databases.

   • pandas: A popular data manipulation library for Python.

   • matplotlib: A widely used library for creating charts and visualizations.

You can install the required libraries using pip:

pip install sqlite3 pandas matplotlib

Steps to analyze and visualize data from SQLite database

Now, let's dive into the steps to analyze and display data from the gold.db database:

Step 1: Connect to the database

First, you need to connect to the SQLite database using the sqlite3 library. Here's how you can do it:

python
import sqlite3
# Connect to the database
conn = sqlite3.connect("gold.db")

Step 2: Query the database to retrieve the required data

query = """
    SELECT
        strftime('%Y-%m', o.OrderDate) AS Month,
        p.MetalType AS ProductType,
        SUM(od.Quantity * od.PriceAtTimeOfPurchase) AS TotalSales
    FROM Orders o
    JOIN OrderDetails od ON o.OrderID = od.OrderID
    JOIN Product p ON od.ProductID = p.ProductID
    GROUP BY Month, ProductType
    ORDER BY Month
"""

Execute the query and fetch the data into a Pandas dataframe:

import pandas as pd 
df = pd.read_sql_query(query, db_connection)

Step 3: Pivot the data for plotting

pivot_df = df.pivot(index='Month', columns='ProductType', values='TotalSales')
pivot_df.fillna(0, inplace=True)

Step 4: Create a chart

Now, it's time to create a chart using the matplotlib library. Let's say you want to create a line chart to visualize the type product prices over time:

import matplotlib.pyplot as pltplt.
# Create a line chartfigure(figsize=(12, 6))
for product_type in pivot_df.columns:
    plt.plot(pivot_df.index, pivot_df[product_type], marker='o', linestyle='-', label=product_type)
    
plt.xlabel('sales Month and year')
plt.ylabel('Total Sales')
plt.title('Total Product Sales by Month')
plt.legend(loc='upper left')
plt.grid(True)
# Rotate x-axis labels for better readability
plt.xticks(rotation=90)
plt.show()

Step 5: Save or display the chart

You can choose to save the chart to a file using plt.savefig("gold_prices_chart.png") or display it within a Jupyter Notebook if you're using one.

That's it! You have successfully analyzed data from the SQLite database and displayed it as a chart in Python. You can adapt these steps to your specific data and charting requirements. Remember to close the database connection when you're done:

# Close the database connection
db_connection.close()

In this blog post, we've covered the essential steps and tools to analyze and visualize data from a SQLite database in Python. Data analysis and visualization are crucial skills for various fields, and Python makes it accessible and powerful for these tasks.