Published in Towards Data Science·Feb 9Member-onlyA Quick Guide to the Dialects of SQLThe 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…Sql5 min read
Published in Towards Data Science·Jan 4Member-onlyHow to Use Set Operations in SQLUnderstanding 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…Sql5 min read
Published in Towards Data Science·Dec 24, 2021Member-onlyDifferent Methods for Pivot Tables in SQLA 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…Sql5 min read
Published in Towards Data Science·Dec 6, 2021Member-onlyCreating Conditional Statements in SQL QueriesA 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…Sql5 min read
Published in Towards Data Science·Nov 23, 2021Member-onlyMastering the OVER Clause in SQLIterations 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…Sql5 min read
Published in Level Up Coding·Jul 16, 2021Member-onlyBuilding a Basic Website with Flask and SQLAlchemyA 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…Python11 min read
Published in Level Up Coding·Jun 14, 2021Member-onlyDrawing on the HTML5 Canvas with a MouseHow 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 Script6 min read
Published in Towards Data Science·Apr 13, 2021Member-onlyClassifying Ships in Satellite Imagery with Neural NetworksA 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 Science8 min read
Published in Towards Data Science·Mar 26, 2021Member-onlyThe Mean Shift Algorithm and Motion ControlsOr, 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 Vision9 min read
Published in Towards Data Science·Mar 10, 2021Member-onlyCreating a Snapchat-Style Filter with PythonA 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 Science10 min read
