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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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4 Built-in functions in SQL Explained Superbly

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Here're four types of built-in functions in SQL. You don't need to create these functions, and these come with your SQL.

sql built-in functions with examples

I am discussing today the SQL functions List.

SQL functions

  1. DATE-TIME functions
  2. Numeric functions
  3. Char functions
  4. Null-related functions

1. DATE-TIME functions
 
These are useful to get DATE and Time. Also, you can covert the DATE and TIME to Char. These are TO_CHAR, CURRENT_DATE, and CURRENT_TIME.


2. Numeric Functions
 
These functions you can use for numeric calculations. Those are TRUNC, SIGN, ROUND, ABS.


3. Char Functions
 
To handle string-related tasks you can use CHAR functions. The CHAR functions are like SUBSTR, CONCAT, LENGTH.

4. NULL related functions
 
To handle null values you can use different functions. Those are COALESCE, NVL, NULLIF

This post covered all your answers for the SQL functions list, SQL built-in functions in Oracle, and SQL functions in any DBMS.


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Summary

I have explained in this post about four different types of SQL built-in functions for your quick reference.

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