1. List, describe, and provide an example of each of the five characteristics of high quality information.
Five characteristics of high quality information include: (a) accuracy; (b) completeness; (c) consistency; (d) uniqueness; and lastly (e) timeliness. The first of the five key elements, accuracy, questions whether all the values are correct, for example, is the name spelled correctly? Is the dollar amount recorded properly? Secondly, completeness questions if all the relevant information is present, i.e. are any of the values missing? An example includes; is the address complete? Does the address have street, city, state and postcode components filled in? The third characteristic, consistency, questions if aggregate or summary information is in agreement with detailed information? For example, do all total fields equal the true total of the individual fields? Fourth in the list is, uniqueness, this characteristic questions if each transaction, entity and event represented only once in the information? For example, are there any duplicate customers? Finally, the last of the five characteristics, timeliness, questions if the information is current with respect to the business requirements? For example, is information updated weekly, daily, or hourly?
2. Define the relationship between a database and a database management system.
A database maintains information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses). Typically, a given database has a structural description of the type of facts held in that database: this description is known as a schema. Alternatively, a database management system is the computer program used to manage and query a database. Hence they are both interlinked as the both interact with one another.
3. Describe the advantages an organisation can gain by using a database.
By using a database in an organisation, businesses can easily maintain and access information as well as accurately and rapidly dispatching orders, increasing flexibility within the firm, increasing scalability and performance; reducing information redundancy; increasing information integrity (quality); and increasing information security.
4. Define the fundamental concepts of the relational database model.
The fundamental concepts in this instance include; entities, entity classes, attributes, keys and relationships. An entity in the relationship database model is a person, place, thing, transaction or event about which information is stored. A table in the relationship database model is a collection of similar entities. Secondly an entity class is the collection of similar entities, and is stored in a different 2d table. Thirdly, attributes, also called fields or columns, are characteristics or properties of an entity class. Each specific entity in the entity class occupies one row in its respective table. The columns in the table contain the attributes. The fourth element, keys, refers to primary and foreign keys. A primary key is a field that uniquely identifies a given entity in a table. For example in customer, the customer ID uniquely identifies each entity in the table and hence is the primary key. On the other hand, a foreign key in the relational database model is a primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables.
5. Describe the benefits of a data-driven website.
The benefits of a data-driven website include: development; content management; future expandability; minimising human error; cutting production and update costs; more efficient; and improved stability. Firstly, development allows the website owner to make changes any time-all without having to rely on a developer or knowing HTML programming. Content management refers to the fact that a in a data-driven website a programmer is not needed to make updates unlike a static website. Future expandability is enabled through a data-driven website, this means that site can grow faster than would be possible with a static site. Minimising human error, a well designed data=driven website will have ‘error trapping’ mechanisms to ensure that required information is filled out correctly and that content is entered and displayed in the correct format. Cutting production and update costs, a data-driven website can be updated and ‘published’ by any competent data entry or administrative person. More efficient, with a data driven solution, the system keeps track of the templates, so users do not have to. Lastly, in terms of improved stability in a data-driven website, there is piece of mind, knowing the content is never lost- even if your programmer is.
6. Describe the roles and purposes of data warehouses and data marts in an organisation.
A data warehouse is a logical collection of information- gathered from many different operational databases- that supports business analysis activities and decision-making tasks. The primary purpose of a data warehouse is to aggregate information throughout an organisation into a single repository in such a way that employees can make decisions and undertake business analysis activities. Therefore, while databases store the details of all transactions and events, data warehouses store that same information but in an aggregated form more suited to supporting decision-making tasks.
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