Consider the Following Relational Database for the Central Zoo ENCLOSURE Relation

question 129

Essay

Consider the following relational database for the Central Zoo. Central Zoo wants to maintain information about its animals, the enclosures in which they live, and its zookeepers and the services they perform for the animals. In addition, Central Zoo has a program by which people can be sponsor of animals. Central Zoo wants to track its sponsors, their dependents, and associated data.
Each animal has a unique animal number and each enclosure has a unique enclosure number. An animal can live in only one enclosure. An enclosure can have several animals in it or it can be currently empty. A zookeeper has a unique employee number. Every animal has been cared for by at least one and generally many zookeepers; each zookeeper has cared for at least one and generally many animals. Each time a zookeeper performs a specific, significant service for an animal the service type, date, and time are recorded. A zookeeper may perform a particular service on a particular animal more than once on a given day.
A sponsor, who has a unique sponsor number and a unique social security number, sponsors at least one and possibly several animals. An animal may have several sponsors or none. For each animal that a particular sponsor sponsors, the zoo wants to track the annual sponsorship contribution and renewal date. In addition, Central Zoo wants to keep track of each sponsor's dependents. A sponsor may have several dependents or none. A dependent is associated with exactly one sponsor.
$$\begin{array} { | l | l | l | l | l |} \hline \text { Enclosure } & & & \text { Date } \\\text { Number } & \text { Type } & \text { Location } & \text { Size } & \text { Built } \\\hline\end{array}$$ ENCLOSURE Relation
$$\begin{array} { | l | l | l | l | l | l | l | } \hline \text { Animal } & & \text { Animal } & & \text { Country } &&\text { Enclosure }\\\text { Number } & \text { Species } & \text { Name } & \text { Gender } & \text { Of Birth } &\text { Weight }&\text { Number } \\\hline\end{array}$$ ANIMAL Relation
$$\begin{array} { | l | l | l | l | } \hline \text { Employee } & \text { Employee } & & \text { Year } \\\text { Number } & \text { Name } & \text { Title } & \text { Hired }\\\hline\end{array}$$ ZOOKEEPER Relation
$$\begin{array} { | l | l | l | l | l |} \hline\text { Animal } & \text { Employee } & \text { Service } & & \\\text { Number } & \text { Number } & \text { Type } & \text { Date } & \text { Time }\\\hline\end{array}$$ CARES FOR Relation
$$\begin{array} { | l | l | l | l | l |} \hline \text { Sponsor } & \text { Social Security } & \text { Sponsor } & & \\\text { Number } & \text { Number } & \text { Name } & \text { Address } & \text { Telephone }\\\hline\end{array}$$ SPONSOR Relation
$$\begin{array} { | l | l | l | l | } \hline \text { Animal } & \text { Sponsor } & \text { Annual } & \text { Renewal } \\\text { Number } & \text { Number } & \text { Contribution } & \text { Date } \\\hline\end{array}$$ CONTRIBUTION Relation
$$\begin{array} { | l | l | l | l | } \hline \text { Sponsor } & \text { Dependent } & & \text { Date of } \\\text { Number } & \text { Name } & \text { Relationship } & \text { Birth }\\\hline\end{array}$$ DEPENDENT Relation
Analyze each of the following situations and, using physical database design techniques, state how you would modify the logical design shown to improve performance or otherwise accommodate it.
a. There is a frequent need to find the total amount of annual contributions expected for each animal from all of each animals' sponsors.
b. There is a high priority need to quickly find the information about the contributions for each animal together with the social security numbers of the sponsors. The sponsor numbers are not required in this query.
c. There is a critical need to quickly list the animals that were born in a particular country.
d. There is a frequent need to be able to retrieve detailed information about an animal together with detiled information about the enclosure in which it is housed.
e. There is a much more frequent and high priority need to access the records for the monkeys than for the other animals.
f. Due to large numbers of access activity, the ANIMAL relation has become a bottleneck.