SQL vs MongoDB: when I reach for each

Relational or document? It is one of the first real decisions you make on a project, so here is how I think about it.

I used SQL for AuraJobs and Nexa because the data was structured and related: users, postings, applications, all linked. SQL's tables and relationships fit that shape, and queries across them stayed clean.

A document store like MongoDB shines when the data is more flexible or nested, and when you read whole documents at once rather than joining many tables.

My rule of thumb as a beginner: if the data has clear relationships and you will query across them, start with SQL; if each record is mostly self-contained and the shape may change, a document database is worth a look.

Written by Khushi Bansal, a final-year Computer Science student at Chitkara University and the founder of Elegant Threads & Beads.