SQL Window Functions - An Introduction

Widow Functions allows you to group rows in a table for in-depth investigation if you are analyzing data in a relational database. Structured Query Language is fantastic for retrieving data, but once you get that data, you need a way to classify it. Window Functions provide a way to obtain sales totals to the current date, group time spent by department, or calculate running totals over data point clusters. We will start with the basics by defining what a window can be and proceed into rankings, calculating quartiles, and how to include aggregate functions. Consider this a mandatory session if you need to crunch numbers from MySQL or PostgreSQL in your job.