1. List, describe, and provide an example of each of the five characteristics of high quality information.
- Accuracy- are all the values correct? eg is the name spelled correctly
- Completeness- Are any of the values missing? eg is the address complete, including street, city, state and postcode
- Consistency- is aggregate or summary information in agreement with detailed information? eg do all total feields equal the true total of the indivual feilds
- Uniqueness- is each transaction, entity and event represented only once in the information? eg are there aby duplicated customers
- Timeliness- is the information current with respect to the business requirements? eg is information updated weekly, daily, or hourly
2. Define the relationship between a database and a database management system.
3. Describe the advantages an organisation can gain by using a database.
Increased flexibilty- databases tend to mirror business structures, and a good database can handle changes quickly and easily, jsut as any good business needs to be able to handle changes quickly and easily
Increased scalability and performance-some organisations must be able to support hundreds or thousands of online users who all want to access information.
Reduced information redundancy - one primary goal of a database is to eliminate information redundancy by recording each peice of information in only one place in the database. This saves space, makes performing information updates easier and improves information quality.
Increased information security- information is an organisation asset that must be protected
4. Define the fundamental concepts of the relational database model.
Entity- an entity in the realtional database model is a person, place, tihng, transaction or event about which information is stored.
Attributes- also called feilds, or columns, are characterstics or propertiess of an entity class
Keys and relationships- primary key- is a feild that uniquely identifies a given entity in a table
- 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.
6. Describe the roles and purposes of data warehouses and data marts in an organisation Development - allows the website owner to make changes at any time, all without having to rely on a developer or knowing HTML programming. A well structured, data-driven website enables updating with little or no information or no training.
Future expandability- having a data driven website enables the site to grow faster than would be possible with a static site
Minimising Human Error- A well desgined, 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 its correct format.
Cutting production costs- convenient and cuts costs, and updates take fraction of time they would with static site
More efficient- system keep track of templates, so users do not have to
Improved Stability- content is never lost, even if your programmer is.
A Data warehouse is a logicall colelction of information, gathered from many differnt operational databases, that supports business analysis activities and decision-making tasks. The primary purpose of a data warehous is to aggregate information throughout an organisation into a single repository for decision-making purposes
A database is the heart of an organisation, it stores key business information like;
- sales data- cutomer, sales, contacts
- inventory data- orders, stocks, delivery
- student data- names, addresses, grades
All businesses use a database of some type. Effective managers know the value of extracting of important data.
A database management system is a group of programs that manipulate the database, and provide an interface between the database and its users and other application programs
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