In SQL, what is the purpose of the "HAVING" clause?

The "HAVING" clause in SQL serves a critical function in filtering results based on aggregate values. Specifically, it is used to apply conditions to groups that have been created by the "GROUP BY" clause. When you aggregate data using functions like COUNT, SUM, AVG, etc., the "HAVING" clause allows you to impose restrictions on those aggregates, much like the "WHERE" clause does for individual rows before grouping occurs.

For instance, if you were to aggregate data to find the average sales by region and only wanted to see regions with an average sales total above a certain threshold, you would utilize the "HAVING" clause. This capability is essential in analysis where insights derived from grouped data must meet specific criteria.

In contrast, the other options represent different functionalities:

• Determining the sort order of results relates to the "ORDER BY" clause, which organizes query results based on specified columns.

• Filtering records before grouping is what the "WHERE" clause accomplishes; it prepares the dataset before any grouping or aggregation takes place.

• Selecting specific columns from multiple tables pertains to the use of "JOIN" operations and "SELECT" statements, not the "HAVING" clause.

This distinction reinforces the purpose of the "HAVING"