Introduction to Data Objects Attributes and Relationships
A Data model consists of three different types of interrelated information data objects attributes that describe an object, and differentiate one object from other and the relationships that connect data objects to one another.
Data Objects: By composite information we mean something that has a number of different properties or attributes which can differentiate it from other information. Data objects represent such composite information which must be familiar to or understood by the software. Thus a single value is not sufficient for a valid data object. But a group of such individual values (e.g. colour weight can collectively) form a valid data object.
A valid data object can be of any type a thing an external entity an occurrence a role an organizational unit a place or a structure. These data objects are related to one another. For example teacher and school are towing data objects. The relationship between them can be defined as the teacher teaches in the school.
A data object encapsulates only data. There is no reference to processes or operations that acts on data within a system.
Attributes: An attributes defines the properties of a data object. It also forms the basis on which two data objects can be distinguished from one another. So attributes can be used to:
Name an instance of a data object,
Describe an instance, and
Make reference to another instance of some other data objects (referencing).
One or more attributes can be collectively used as an identifier of a particular entity of a data object. Such collective attributes are known as keys. Referring to a data object student a reasonable identifier must be his school college ID number.
Relationships: Every data object defined in a system are interrelated to one another (may be not to all) in some ways. Relationships are generally bidirectional, which can be either shown as both sided arrows and no arrows on both sides. For example, consider tow data objects medicine and medicine store. Their relationship is shown in fig 4.2.
A set of object relationship pairs can be defined between these two objects:
A medicine store orders medicine.
A medicine store displays medicine.
A medicine store stocks medicine.
A medicine store sells medicine.
A medicine store returns medicine.
Latest technology based Software Engineering Online Tutoring Assistance
Tutors, at the www.tutorsglobe.com, take pledge to provide full satisfaction and assurance in Data Objects Attributes and Relationships homework help via online tutoring. Students are getting 100% satisfaction by online tutors across the globe. Here you can get homework help for Data Objects Attributes and Relationships, project ideas and tutorials. We provide email based Data Objects Attributes and Relationships homework help. You can join us to ask queries 24x7 with live, experienced and qualified online tutors specialized in Data Objects Attributes and Relationships. Through Online Tutoring, you would be able to complete your homework or assignments at your home. Tutors at the TutorsGlobe are committed to provide the best quality online tutoring assistance for Software Engineering homework help and assignment help services. They use their experience, as they have solved thousands of the software engineering assignments, which may help you to solve your complex issues of Data Objects Attributes and Relationships. TutorsGlobe assure for the best quality compliance to your homework. Compromise with quality is not in our dictionary. If we feel that we are not able to provide the homework help as per the deadline or given instruction by the student, we refund the money of the student without any delay.
Concept of Divide and Conquer algorithm-Assignment help and Homework help including the key concepts of Steps of Divide and Conquer, Binary Search, Effectiveness of binary search, Optimizing source code, Pre-Computation, Pre-Calculation, Decomposition and Symmetries.
tutorsglobe.com immunological basis of graft rejection assignment help-homework help by online tissue transplantation tutors
Redox titration-potassium permanganate as oxidant tutorial all along with the key concepts of Experiment of redox titration, Procedure of redox titration, result of redox tritration
tutorsglobe.com ecg-pqrst wave assignment help-homework help by online ecg-electrocardiogram tutors
Explain inventory control - define Perpetual Inventory System, ABC System, Just in Time Inventory, VED Analysis, and FSND Analysis.
Get affordable Integrated Marketing Communication Assignment Help from industry best qualified tutors for scoring notable grades.
tutorsglobe.com rent-marginal-wages theory of profit assignment help-homework help by online theories of profit tutors
A tangible non-current asset comprises both a physical life and an economic life. While a business disposes of a tangible non-current asset which may still be of value to others, some payment might be received.
the basic principle of prototype model is that a throwaway prototype is built to help in understanding the requirement during the requirement analysis phase only.
tutorsglobe.com mechanism of ascent of sap assignment help-homework help by online water transport tutors
Theory and lecture notes of Short-Run Aggregate Supply all along with the key concepts of short-run aggregate supply, Money Stock, Money Market, LM Curve. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Short-Run Aggregate Supply
tutorsglobe.com skin assignment help-homework help by online receptor organs tutors
Elements of Group 15 tutorial all along with the key concepts of Occurrence, Extraction and Uses of group 15, General Characteristics of Group 15, Physical-Chemical Properties of group 15 elements and Allotropic Forms of Phosphorus
Theory and lecture notes of Economics of Information all along with the key concepts of economics of information, Problem of agency, asymmetric information, Theory of a Firm, stylized firm. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Economics of Information.
Avail unsurpassed Operating System Assignment Help service from 24x7 available top-rated tutors at viable prices to score high grades.
1931111
Questions Asked
3689
Tutors
1463709
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!