From Tables to Trends: Understanding Joins and Window Functions in SQL

What is SQL used for? SQL (Structured Query Language) is primarily used for managing and manipulating data in relational databases. It is the common language for communicating with databases such as Oracle, Microsoft SQL Server, PostgreSQL, and MySQL, allowing users to carry out a variety of operations from simple data management to intricate analysis. JOINS In SQL, a JOIN clause is used to combine rows from two or more tables based on a related column between them. The primary purpose of joins is to retrieve data that has been spread across multiple tables in a relational database, providing a comprehensive, unified view in a single result set. It helps answer business questions like which customer placed an order or which product generated revenue. Window Functions SQL window functions perform calculations across a set of table rows related to the current row, without merging those rows into a single output like a GROUP BY clause would. They return a result for each individual row, w