Intoduction to Entity Relationship Diagram
Entity Relationship Diagram represents the object relationship pairs in graphical forms thus we can say that the primary goal of E-R diagram s is to represent data objects along with their relationship. The various components of data modelling described above forms the primary components of entity relationship diagram.
ER model for data uses three features to describe data:
Entities: which specify distinct real world items in an application?
Relationships: connecting different entities and representing meaningful dependencies between them.
Attributes: which specify various properties of entities and relations involved in a system.
In ER diagram data objects are represented by labelled rectangle. All its attributes are represented by labelled ellipse connected to data objects by straight line. There are two ways in which relationships are represented in an ER diagram. One way is to use a labelled straight line. Another also knows as conventional way is to use a labelled diamond connected to dependent data objects by straight line.
These two ways are shown in fig 4.6, where an employee works in a company. The attributes of two entities are also shown.
In addition to basis ER notations an analyst can represent data object type hierarchy. For example data object mobile phone can be categorised as GSM color display and camera with color display which can further be categorised. It is shown in fig4.7.
ER diagram provides the most convenient way examining data within the context of software.
Latest technology based Software Engineering Online Tutoring Assistance
Tutors, at the www.tutorsglobe.com, take pledge to provide full satisfaction and assurance in Entity Relationship Diagram homework help via online tutoring. Students are getting 100% satisfaction by online tutors across the globe. Here you can get homework help for Entity Relationship Diagram, project ideas and tutorials. We provide email based Entity Relationship Diagram homework help. You can join us to ask queries 24x7 with live, experienced and qualified online tutors specialized in Entity Relationship Diagram. 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 Entity Relationship Diagram. 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.
tutorsglobe.com muscles assignment help-homework help by online human physiology tutors
Systematic Classification of Bacteria tutorial all along with the key concepts of Bergey's Manual of Systematic Bacteriology, Spirochetes, Gram-Negative Rods, Ordinary Gram-Positive Bacteria, Gram-positive filamentous bacteria, Streptomyces and correlated genera
tutorsglobe.com racemose inflorescence assignment help-homework help by online inflorescence tutors
Chemical methods of controlling Microbial growth tutorial all along with the key concepts of Definition of Disinfection, Antimicrobial Agents, Ideal Antimicrobial Agent or Disinfectant, Chemical Antimicrobial Agents, Phenolics, Alcohols, Halogens and Quaternary Ammonium Compounds
radioactive decay processes tutorial all along with the key concepts of kinetics of radioactive decay, decay mode and energy, chain reaction, nuclear fusion reactor and nature of radiation
tutorsglobe.com amorphous solids assignment help-homework help by online solid state chemistry tutors
Theory and lecture notes Solution Instability for the Explicit Method all along with the key concepts of differential equations, Difference Equations in Matrix Form. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Solution Instability for the Explicit Method.
alkaline earth metals tutorial all along with the key concepts of extraction of alkaline earth metals, uses of alkaline earth metals, physical properties, solubility, lattice energy and hydration energy
Theory and lecture notes of Numerical Differentiation all along with the key concepts of functions and data, Approximating derivatives from data, Errors of approximation, Partial Derivatives. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Numerical Differentiation.
www.tutorsglobe.com offers answering questions to policies for reducing unemployment, theory of concepts of unemployment, economics assignment help- homework help.
tutorsglobe.com uses of biogas assignment help-homework help by online recycling of waste tutors
tutorsglobe.com hybridization assignment help-homework help by online atomic structure tutors
polyurethane tutorial all along with the key concepts of properties of polyurethane, advantages of polyurethane, applications of polymers, usage per application of polymer
tutorsglobe.com regions of a typical root assignment help-homework help by online root system tutors
The limitations of traditional costing system - In a conventional costing system, overheads that are indirect costs are allocated, apportioned and at last absorbed in the cost units.
1949187
Questions Asked
3689
Tutors
1446375
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!