abstract base classA class that defines the requirements and behavior of descendant classes by specifying methods and variables. An abstract base class does not support the creation of instances.

Related termsclass, descendant class, method, variable

Contrast withobject

abstractionA technique that reduces duplication of program code. Abstraction provides a framework for related classes in an object-oriented system.

Related termsclass, object-oriented programming

aggregate functionA function that performs a calculation over a set of data rows. For example, SUM calculates the sum of values of a specified numeric field over a set of data rows. Examples of aggregate functions include AVERAGE, COUNT, MAX, MIN, and SUM.

Related termsdata row, ...

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