1:1 Shorthand for a one-to-one relationship.

1:M Shorthand for a one-to-many relationship.


Abstract class A class from which no objects are created.

Abstract data type In an object-oriented environment, a user-defined data type; a class.

Accessor method A function that returns the values of private data stored about an object.

Aggregate function A SQL function—for example, AVG and SUM—that computes a variety of measures based on values in one or more numeric columns.

Aggregation In an object-oriented environment, a class that manages objects created from another class.

All-key relation A relation in which every column is part of the primary key.

American National Standards Institute (ANSI) The US body that approves standards for many ...

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