Introduction
Database的第二次作业代写，比较基础，将前次的UML图，转换成关系型数据库的模型。
需要注意的地方是UML图中的数据类型，转换成关系型数据库中的字段类型时，需要做一定的修改，比如string类型在关系型数据库里面可以是varchar类型。
The Database Design Process
Develop a schema to manage a set of Web forms composed of several Web input
fields: text field, text area, select, radio, check boxes, date, and time.
Each Web form is created by a developer for a particular Web application and
is intended to be filled in by a particular user. Anonymous users can fill in
Web forms as well. All fields have a name and can have several values. Text
fields can be configured to have a type of number, string, URL, or email. Text
fields also have a max size. The default type is string. This is used for
validation purposes. Text area can have a number of rows and columns and a
maximum number of characters. Date and time fields can have a min and max or
no limitations at all. Select, radio and check boxes require a set of values
and labels from which a user can chose. The labels are used to display the
values in human readable prose. The user can select a single value from radio
fields, but can choose several values from select and check box fields. The
fields can be arranged in a particular order. Fields have associated
descriptive labels that appear next to the field, and tooltips that appear
when users hover over the field for help. The database is used to render the
forms to be filled by a user. When the user fills in and submits the form, the
data is stored in such a way that groups the application, form, user, date
submitted, fields, and values. Submissions are used to generate reports in the
form of Excel spreadsheets.
Create a class diagram that captures the data described above. Apply the data
analysis techniques that were discussed in class. Clearly annotate your class
diagram using classes, attributes, cardinality, associations, the name of the
relationship, aggregation, composition, and generalizations. Apply the
techniques described in class to convert the class diagram to a relational
model and write the equivalent SQL create statements. Argument, and defend
your choices as you apply the analysis.
Grading
- (40pts) Class Diagram
- (10pts) Generalization, Aggregation or Composition (1 to or 1 to 1.. ) (if applicable, explain)
- (10pts) Correct Data Types, e.g., Date, String, Integer, List, Array, Enumeration, etc.
- (10pts) Cardinality
- (10pts) Reify: revise Weak-Weak and strong-strong relationships (if applicable, explain)
- (50pts) Schema
- (10pts) Primary Keys, required, artificial keys vs. natural keys
- (10pts) Foreign Keys
- (10pts) Primary Keys that are also Foreign Keys (if applicable, explain)
- (10pts) Delete Cascade (if applicable, explain)
- (10pts) Correct Data Types, e.g., DATE, VARCHAR, etc.
- (10pts) Prose: defend your assumptions and how they guided your decisions
