How do SQL date functions affect query performance?

How do SQL date functions affect query performance?

SQL date functions can significantly impact performance, especially on large datasets. Using functions on indexed columns can lead to full table scans.

What are some best practices for using date functions in SQL?

Best practices include avoiding functions on indexed columns, using date ranges instead of functions, and leveraging built-in date functions efficiently.

Can you give an example of a slow query using date functions?

Sure! A query like SELECT * FROM orders WHERE YEAR(order_date) = 2023 can be slow because it applies a function to the indexed column.

What alternatives can I use to improve performance?

You can rewrite the query to use a date range, like SELECT * FROM orders WHERE order_date >= '2023-01-01' AND order_date < '2024-01-01'.