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Why is it that many software developers don't pay enough attention to requirements engineering? Are there ever circumstances where you can skip it?
What are the four design models required for a complete specification of a software design? Describe the role of one of them in your own words.
The four design models are data design, architectural design, procedural design, and interface design.
In the process of data design, you need to define data models, entity types, attributes, and relationships. To design relational database, which is the most widely used data model, you will create data specification such as data definitions and E-R diagrams.
You can use different data models depending on types and purposes of data. If you need to read and write database records very often, for instance, if you treat HTTP sessions in a database, key-value stores can be more faster. In case you analyze large amounts of numerical data such as point-of-sales data, column-oriented data warehouse is more efficient.
