{{tag>Index Glossary Aggregate}}
===== Aggregate operation =====

An aggregate operation performs arithmetic calculations on several [[glossary:business_object|business objects]] and/or their [[glossary:attribute|attribute]]. An example of an aggregate operation would be counting the number of items in an order. Another example is calculating the order amount as a total of the amounts of all items in the order. There are several aggregate operations in the [[glossary:rule_language|rule language]].