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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...
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3 SQL Query Examples to Create Views Quickly

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There are three kinds of Views in SQL. The three views are Read-only, Force, and Updatable. Views real usage is to hide data. And you need to ensure base tables are present before you create a View.


You can call views as logical tables. The advantage of Views is you can show only some of the fields of base tables.


What is a View in SQL
  • A view can be constructed with another view so it is called a nested view.
  • You can create or replace an existing view
  • A view can be created without having base tables. This is possible with the FORCE option.
#1: Read-Only Views

The standard syntax for the view is as follows:

CREATE OR replace VIEW invoice_summary AS
SELECT vendor_name count(*) AS invoice_count,
SUM(invoice_total) AS invoice_total_sum
FROM vendor
JOIN invoices
ON vendors.vendor_id*invoices.vendor_id
GROUP BY vendor_name;

Notes: You cannot update Read-only Views


#2: Force Views

CREATE FORCE VIEW products_list
AS
SELECT product_description,
product_price
FROM products;

Notes: Without base Table you can create a FORCE View.


#3: Updatable Views

A view can be updatable if a view follows certain rules.

A view when it is created for update purpose, you can give INSERT, UPDATE and DELETE operations.

A read-only view should contain WITH  READ ONLY clause

While updating a view, it is possible to update only one base table at a time. When you created a view from more than one table, then it is not possible to update two tables at a time.


How to Manipulate Views 

ALTER View

  • CREATE OR REPLACE statement you can use to ALTER the View.

Drop View

  • Drop view vendor_sw

Summary

A view with CHECK OPTION restricts to update. When condition satisfied it updates.

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