What are the features of the MYSQL GROUP BY statement?

The GROUP BY statement in MySQL is used to group the result set based on one or more columns. Here are the characteristics of the GROUP BY statement:

1. Grouping: The GROUP BY statement organizes the result set into groups based on the specified column. Rows with the same value are grouped together.
2. Aggregate functions: GROUP BY statements are typically used in conjunction with aggregate functions (such as SUM, COUNT, AVG, etc.) to calculate summary values for each group.
3. Sorting: The GROUP BY statement can be combined with the ORDER BY clause to sort the grouped results. For example, the grouped results can be sorted in ascending or descending order based on a specific column.
4. Filtering: The GROUP BY statement can be used in conjunction with the HAVING clause to filter the results of a group. The HAVING clause is similar to the WHERE clause, but it is used for filtering the results after grouping.
5. The output: The result of the GROUP BY statement is a summary based on grouping. Each group will be represented by the values of one or more columns.
6. Multi-column grouping: The GROUP BY statement can group data based on multiple columns. In this scenario, the results will be grouped according to the specified combinations of columns.

It is important to note that when using the GROUP BY statement, the columns in the SELECT clause must be grouping columns, aggregate functions, or non-aggregate expressions.