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Published in Towards Data Science

·Feb 9

A Quick Guide to the Dialects of SQL

The Difference between T-SQL, PL/SQL, PL/pgSQL, and More — First developed in the 1970s and made widely available in the 1980s, SQL quickly grew to become the industry standard method of communicating with databases. Only recently threatened by the rise of NoSQL, SQL remains an prevalent force and a prerequisite for any data professional. Since its initial release, however…

Sql

5 min read

A Quick Guide to the Dialects of SQL
A Quick Guide to the Dialects of SQL

Published in Towards Data Science

·Jan 4

How to Use Set Operations in SQL

Understanding the UNION, INTERSECT, and EXCEPT Operators — Data professionals often need to collect information from multiple sources. While the concepts of JOINS are taught extensively and covered frequently in interview questions, their close cousins, set operators, don’t often receive the same amount of attention. Both methods gather data from multiple sources, either tables of subqueries. JOINS return…

Sql

5 min read

How to Use Set Operations in SQL
How to Use Set Operations in SQL

Published in Towards Data Science

·Dec 24, 2021

Different Methods for Pivot Tables in SQL

A Guide to Pivots and Cases to Summarize Data — Data professionals often look at transactional data and need a pivot table for further analysis. For example, a banking expert might need to review each transaction to determine how certain accounts settle or a sales analyst might need to review individual transactions to determine how well certain products sell. A…

Sql

5 min read

Different Methods for Pivot Tables in SQL
Different Methods for Pivot Tables in SQL

Published in Towards Data Science

·Dec 6, 2021

Creating Conditional Statements in SQL Queries

A Quick Guide to the IF, CASE, and IFNULL Statements — Although SQL isn’t a general-purpose language, it includes conditional statements with a similar structure to other languages. The classic IF and CASE statements permit for the ability to change data on the query-level instead of modifying them in another environment, such as a worksheet or a data frame. While neither…

Sql

5 min read

Creating Conditional Statements in SQL Queries
Creating Conditional Statements in SQL Queries

Published in Towards Data Science

·Nov 23, 2021

Mastering the OVER Clause in SQL

Iterations Over Rows of Data — As demand for them grew, more databases integrated window functions to perform calculations on subsets of data. Using the same principle as the sliding window technique, window functions calculate how a single data point compares to either the rest of the data set or just a portion of it. In…

Sql

5 min read

Mastering the OVER Clause in SQL
Mastering the OVER Clause in SQL

Published in Level Up Coding

·Jul 16, 2021

Building a Basic Website with Flask and SQLAlchemy

A Quick Tutorial for Creating a Bare Minimum Backend — Flask is a lightweight and incredibly flexible framework for creating website backends in Python. In addition to abstracting difficult web concepts, such as routing, rendering HTML documents, and handling static files, it’s easy to integrate with any of Python’s many libraries. To show its power, this tutorial will develop a…

Python

11 min read

Building a Basic Website with Flask and SQLAlchemy
Building a Basic Website with Flask and SQLAlchemy

Published in Level Up Coding

·Jun 14, 2021

Drawing on the HTML5 Canvas with a Mouse

How to Use the Canvas as an Art Tool — The canvas element in HTML5 is a great, versatile tool that allows the creation of both 2D and 3D graphics. Used for everything from hosting pictures to outright gaming, there’s no shortage for creativity in its application. With some vanilla JavaScript, a literal blank canvas can be given to draw…

Java Script

6 min read

Drawing on the HTML5 Canvas with a Mouse
Drawing on the HTML5 Canvas with a Mouse

Published in Towards Data Science

·Apr 13, 2021

Classifying Ships in Satellite Imagery with Neural Networks

A Lesson in How to Train a CNN from Scratch — Nothing tells of the ubiquity of satellite imagery like Google Maps. A completely unpaid service provides anyone with internet access a entire planet’s worth of satellite imagery. While Google Maps is free, other paid alternatives exist which take photos of the earth’s surface on a more frequent basis for commercial…

Data Science

8 min read

Classifying Ships in Satellite Imagery with Neural Networks
Classifying Ships in Satellite Imagery with Neural Networks

Published in Towards Data Science

·Mar 26, 2021

The Mean Shift Algorithm and Motion Controls

Or, How I Used a Tennis Ball to Play Pacman — I’ve written about the Mean Shift Algorithm before, but I never gave a practical application of it. I ultimately felt unsatisfied by the article, so I wanted to revisit the topic and apply it to a real world situation. The Mean Shift algorithm can track objects in real time by…

Computer Vision

9 min read

The Mean Shift Algorithm and Motion Controls
The Mean Shift Algorithm and Motion Controls

Published in Towards Data Science

·Mar 10, 2021

Creating a Snapchat-Style Filter with Python

A Practical Demonstration of Haar Cascades and Homography — The introduction of augmented reality (AR) in smart phones ushered a novel approach to entertainment. From playing games like Pokémon Go to making funny faces on Snapchat, AR has become a commonplace phenomenon. While these technologies seem advanced enough to borrow from science fiction, creating a fun, Snapchat-style filter in…

Data Science

10 min read

Creating a Snapchat-Style Filter with Python
Creating a Snapchat-Style Filter with Python
Andrew Udell

Andrew Udell

Data Science Enthusiast | Code Junkie | Lifelong Student https://www.linkedin.com/in/andrew-udell-108802140/

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