5.1. The database DAT as a system

5.1. The database DAT as a system

The data model of the digital basic map is the ensemble organized according to uniform principles of object sorts finite number, their attribute sorts of finite number also by single one and their relationship type general theoretical structure of the database DAT, its abstract representation.

This chapter provides the description of the above three factors (object, attribute, relation) of the database and of the organized relations of these factors.

By forming the concrete object, thing or phenomenon to be described of the real world with knowledges in the database DAT digital map object, shortly object is obtained. For abstract denoting of the object serves the expression "object sort". Two groups of descriptive knowledges related to objects are distinguished. One of them is the attribute, which encompasses the identification, thematical, positional and data quality features of the object. For abstract denotation of some descriptive feature is used the expression "attribute type". To each of the attribute types belongs a defined set of the concrete attribute values.

The other descriptive knowledge is the relationship to be expressed in the database DAT between two or more objects, or object and its geometrical elements. For the abstract denotation of this is used the relationship type which becomes concrete in relationship occurrence.

The database DAT is a system of so called topological structured vector data the geometrical elements ensure the full and consistent topological forming of the object of the space in the plane by means of one or multi direction topological relationship. The system of the topological structured vector data is described in the sub-chapters 5.3., 5.4. and 5.6.

Beside the topologically structured vector data there appears in the database DAT also the so called system of the data of matrix structure, which is used in case of relief for forming of the third dimension of the space, the height in form of digital terrain model. The description of the data model of a matrix structure can be found in sub-chapter 5.7.

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