$group

The $group aggregation stage groups documents by specified identifier expressions and applies accumulator operators like $sum, $avg, $max, $min, and $push. It's essential for data aggregation, calculating statistics, and creating summary reports. $group can group by single or multiple fields and supports complex expressions for dynamic grouping criteria.

Visit the following resources to learn more:

• @official@Aggregation Operators
• @official@$group
• @article@MongoDB $group (aggregation) Usage with Examples