Efficiency of Algorithms in Database System

Abstract

Pick any web application you use daily — whether it's a banking portal, a ride-hailing service, or an online store — and somewhere behind the scenes, a database is doing a lot of heavy lifting. What often goes unnoticed is that the speed and reliability of these systems hinge not just on hardware, but on the specific algorithms chosen to store, retrieve, and process data. This paper examines that relationship in detail. We look at indexing structures, query planning, sorting and hashing techniques, join processing strategies, and how concurrency is managed when dozens or thousands of users access the same data at once. The goal is to give a clear picture of why some algorithmic choices lead to systems that scale gracefully, while others buckle under load.