Aggregation in DBMS refers to the process of combining two or more entities that cannot be used alone to form a more meaningful entity. The specific entities are combined because they do not make sense on their own. Aggregation creates a relationship that combines these entities to establish a single entity that makes sense and enables the system to function well. In aggregation, the relation between two entities is treated as a single entity, and the relationship with its corresponding entities is aggregated into a higher-level entity. Aggregation is an abstraction through which relationships can be represented as higher-level entity sets.
Aggregation is used to perform DBMS aggregation operations when using data in the form of numerical values. The following operations can be used to perform DBMS aggregation: COUNT, SUM, AVG, MIN, and MAX.
Aggregation in a database management system helps to ensure that all entities are utilized within the system. Without this operation, trivial entities may become inoperative. Multiple aggregations within a database management system ensure that the entire system is fully functional.
