What are common performance bottlenecks in SQL queries?

< 1 min read

Common performance bottlenecks in SQL queries include missing indexes on frequently filtered or joined columns.
In one project, a report was slow because joins were done on non-indexed fields.
Using SELECT * instead of required columns increased unnecessary data load.
Complex subqueries and nested queries caused longer execution time.
Large table scans happened when WHERE conditions were not optimized.
Improper joins like many-to-many without filters increased data duplication.
Using functions in WHERE clauses prevented index usage.
After query tuning and indexing, report load time improved significantly.

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