What is indexing and how does it improve query performance?

< 1 min read

Indexing is creating a structured reference on specific columns to speed up data retrieval.
In my project, we added indexes on frequently filtered columns like Order Date and Customer ID.
Without index, the query scanned the entire table, which slowed the dashboard.
After indexing, SQL directly located required records instead of full table scan.
It significantly reduced execution time for joins and WHERE conditions.
We avoided over-indexing because it increases storage and affects insert/update performance.
We analyzed query execution plan before deciding which columns to index.
Overall, proper indexing improves speed and report responsiveness.

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