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Database Indexing: The Performance Trick Nobody Explained Properly
Your queries are slow because you don’t understand indexes. Let’s fix that in 15 minutes.
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Here’s a scenario I’ve seen dozens of times.
A developer builds an app. It works great in development with 100 users. Then it goes to production, gets 100,000 users, and suddenly everything is slow. Pages timeout. The database CPU is at 100%. Users are complaining.
The developer starts optimizing code. Caching everything. Adding more servers. Nothing helps.
Then someone looks at the database and says, “Have you tried adding an index?”
One line of SQL later, queries that took 30 seconds now take 30 milliseconds. Problem solved.
Database indexing is the single highest-leverage performance optimization most developers ignore. It’s not sexy. It’s not a new framework. But it can make your app 100x faster with almost no code changes.
This guide explains how indexes actually work, when to use them, and the mistakes that destroy performance. By the end, you’ll understand indexes…
