Attributwert

Attributwert is a German term used in data modeling, databases and information systems to denote the value contained in a single attribute of a data record or entity. In relational databases, an Attributwert is the concrete item stored in a column for a given row, i.e., the projection of a tuple onto an attribute. Each attribute has an assigned domain or data type (such as integer, string, date), and the Attributwert must conform to this type. The collection of Attributwerte across all attributes defines a data record or tuple.

In normalization, attributes should hold atomic values; the first normal form requires that an Attributwert is indivisible with respect to the domain. Null values can occur, representing missing or unknown information; handling and propagation of nulls depend on the database system and query language.

In practice, Attributwerte are used in queries, forms, and data exchange. They may be literal values, such as numbers or text, or references to other entities in relational or object databases. In RDF and semantic models, the term can correspond to a property value: for a subject, the Attributwert is the object of a triple.

Quality and integrity of Attributwerte are maintained by type enforcement, constraints, validation rules, and proper data modeling. When designing data schemas, clear attribute names and defined domains help ensure consistent attribute values across records.