The HAVING clause is used to filter the results of aggregated queries after the GROUP BY clause has been applied. It enables users to set conditions on aggregated values, making it possible to refine results based on calculations. The syntax for HAVING is: SELECT column_name, aggregate_function(column_name) FROM table_name GROUP BY column_name HAVING condition;. For example, to find departments with more than 10 employees, you could use:
sqlCopy codeSELECT department_id, COUNT(*) FROM employees GROUP BY department_id HAVING COUNT(*) > 10;
This query will return only those departments that meet the specified criteria, allowing for more focused analysis. The HAVING clause is particularly useful in scenarios where you want to apply conditions to aggregated data, enhancing the effectiveness of reporting and decision-making.
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