LOGICIAL DESIGN PART 1
CIS111 Intro to Database Mgt Systems
April 20, 2013
The ACME Global consulting will provide software development solutions, offer advice and support and structure within a company. From short to long term project as well as small to large sized businesses and corporations. The main components that apply to this are having a set of domains and sets that represents data structure, Integrity of rules that ensures data protection and operations that will carry on data. The company needs to have an understanding of data and functional needs of the company. The relational model can be used with both databases and the management ...view middle of the document...
The data we collect about the entity is the attribute.
Relationship - It defines how two or more entities are related to each other.
There are different relationships that exist in E-R modeling. One to One relationship, One to Many relationship, Many to one relationship, and many to many relationship.
Keys - Allow us to tell records apart. There are three kind of keys. Superkey, Candidate keys and primary keys. Superkeys uniquely identify an entity. Candidate keys are ones that does not contain extra attributes. Primary keys are identifying a candidate key.
The enhanced E-R model is an enhancement of the basis E-R model. It contains classes, data types, generalization, and specialization concepts that are not provided in E-R model. Acme global consulting could benefit from using EER. The model would be more clearly reflect the data requirements of the system. EER will lay out all the basic details of the data requirements.
The requirements must be clearly understood in order to develop sophisticated diagrams in complex requirements. Relational model uses the (SQL) standard query language. Relational databases established defined relationships between...