Performance issues often occur due to poor query design.
Many problems can be avoided with basic optimization knowledge.
Understanding mistakes helps improve system speed.
One common mistake is using SELECT * in large tables.
This retrieves unnecessary data.
It increases memory usage and execution time.
Another mistake is missing indexes on frequently searched columns.
Without indexes, full table scans occur.
This slows down queries significantly.
Using functions on indexed columns disables index usage.
This causes the optimizer to ignore indexes.
Query becomes slower.
Avoiding common mistakes greatly improves performance.
Proper indexing and query design are essential.
Performance tuning is a continuous process.