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How to Read a CSV File from Amazon S3 Using Python (With Headers and Rows Displayed)

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  Introduction If you’re working with cloud data, especially on AWS, chances are you’ll encounter data stored in CSV files inside an Amazon S3 bucket . Whether you're building a data pipeline or a quick analysis tool, reading data directly from S3 in Python is a fast, reliable, and scalable way to get started. In this blog post, we’ll walk through: Setting up access to S3 Reading a CSV file using Python and Boto3 Displaying headers and rows Tips to handle larger datasets Let’s jump in! What You’ll Need An AWS account An S3 bucket with a CSV file uploaded AWS credentials (access key and secret key) Python 3.x installed boto3 and pandas libraries installed (you can install them via pip) pip install boto3 pandas Step-by-Step: Read CSV from S3 Let’s say your S3 bucket is named my-data-bucket , and your CSV file is sample-data/employees.csv . ✅ Step 1: Import Required Libraries import boto3 import pandas as pd from io import StringIO boto3 is...

5 SQL Queries That Popularly Used in Data Analysis

 Here are five popular SQL queries frequently used in data analysis.


5 SQL Queries Popularly Used in Data Analytics




1. SELECT with Aggregations

Summarize data by calculating aggregates like counts, sums, averages, etc.

SELECT department, COUNT(*) as employee_count, AVG(salary) as average_salary
FROM employees
GROUP BY department;


2. JOIN Operations

 Combine data from multiple tables based on a related column.

SELECT e.employee_id, e.name, d.department_name
FROM employees e
JOIN departments d ON e.department_id = d.department_id;

3. WHERE Clause for Filtering

Filter records based on specified conditions.

SELECT *
FROM sales
WHERE sale_date BETWEEN '2024-01-01' AND '2024-12-31'
  AND amount > 1000;

4. ORDER BY Clause for Sorting

Sort results in ascending or descending order based on one or more columns.

SELECT product_name, price
FROM products
ORDER BY price DESC;

5. GROUP BY with HAVING Clause

Group records and apply conditions to the aggregated results.

SELECT department, SUM(salary) as total_salaries
FROM employees
GROUP BY department
HAVING SUM(salary) > 50000;

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