An advantage of database systems is that you needn’t perform frequent updates and apply latest patches. A _____ key can be described as a minimal superkey, a superkey without any unnecessary attributes. in the video, what does the officer recommend you do if it’s dark outside during the traffic stop? In a _____ diagram, the arrows above the attributes indicate all desirable dependencies. A _____ database supports a relatively small number of users or a specific department within an organization.
A data structure is a way of storing data in a computer so that it can be used efficiently. It is an organization of mathematical and logical concepts of data. Often a carefully chosen data structure will allow the most efficient algorithm to be used. The choice of the data structure often begins from the choice of an abstract data type. A different approach is to use adaptive systems such as artificial neural networks that can autonomously create implicit models of data. For each instance of entity A, there may or may not exist instances of entity B.
T/f A composite identifier is a primary key composed of more than one attribute. In the original Chen notation, each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line. If an employee within an EMPLOYEE entity has a relationship with itself, that relationship is known as a _____ relationship. In organizations that generate large number of transactions, _____ are often a top priority in database design. Entities represent real world things; they can be conceptual as a sales order or physical such as a customer. We can deduce from this that the nature of the relationship between members and payments entities is one-to-many.
The mandatory nature of the relationship for the agent is shown by the solid circle; the hollow circle indicates an optional relationship for a performer. This means that there must be a relation to represent performers, another relation to represent agents, and a third relation to represent those occasions when performers have booked through agents. The links between performers and agents are shown by having the agent identifier stored against the appropriate performer in the third relation. A physical data model, which provides the blueprint for a physical manifestation — such as a relational database — of the logical data model.
_____ serve as the intermediary between the user and the database. A performer might have one or more bookings; each booking must involve one performer. A performer must have one or more bookings, but a booking might not involve a performer (e.g. a booking might be for an exhibition, not a performer). A performer must have one or more bookings; each booking must involve one performer. Analyse a given situation to identify the entities involved. These together can be the PK in the S table OR these together with another simple attribute in the new table R can be the PK.