POLYMORPHISM OF CLASSES AND REFERENCE OF INSTANCES DISTRIBUTION FOR ECONOMIC OBJECTS IN APPLICATIONS
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Authors:
• Emilia VASILE, email: Athenaeum University, Bucharest, Romania, Afiliation: rector@univath.ro
• Dănuţ-Octavian SIMION, email: danut_so@yahoo.com, Afiliation: Athenaeum University, Bucharest, RomaniaPages:
• 9|21 -
Keywords: polymorphism, specific classes, economical data, derived classes, business flows, application modules, analysis of data
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Abstract:
The paper presents the polymorphism of classes and reference of instances distribution for economic objects in applications. Data stored in a database is persistent data, ie data that remains stored on magnetic media, independent of the execution of application programs. Persistent database data is entered, deleted, or updated using input data (from the keyboard, from reading data files, or from receiving messages). Input data is generally non-persistent data; they are generated by users and are stored (becoming persistent data) only after they have been validated (accepted) by the DBMS. The output data of a database system is also non-persistent data; they come from database query operations and are made available to the user (in the form of impressions, printed reports, etc.). The correspondent model for database tables and entities are classes that encapsulate properties and methods. Data - acts as a bridge between machine components (hardware and software) and the human component. The database contains both operational data (the set of records being worked on) and metadata. Polymorphism can obtain new objects derived from existing classes that map custom business logic which includes specific economic operations. The data model is defined as a set of concepts used in the description of the data structure. The structure of the database means the type of data, the connection between them, the restrictions applied to the data.
