Database Systems: Design, Implementation, and Management: Chapter 1 Review Questions – Flashcards

Data: raw facts Field: an attribute, same data type Record: related data that describes an entity File: a collection of related records.

Data redundancy occurs when the same data are stored in multiple places unnecessarily. The use of spreadsheets and tables in different parts of the organization can cause it.

Data independence exists when you can change the data storage characteristics without impeding the program's ability to access the data.

DBMS = Database Management System a collection of programs that manages the database structure and controls access to the data stored in the database. (think electronic filing cabinet) functions of a DBMS: data dictionary management data storage management data transformation and presentation security management multi user access control backup and recovery management data integrity management database access languages and application programming interfaces. database communication interfaces.

When it is possible to make changes in the file structure without affecting the application program's ability to access the data.

Data are raw facts that have not been processed. Information is data that has been processed and given context. Databases help to facilitate the manipulation of data to create information by providing an organizational structure that makes relationships and connections between data explicit.

serves as the intermediary between the user and the database. advantages: improved data sharing improved data security better data integration minimized data inconsistency improved data access improved decision making increased end-user productivity disadvantages: increased costs management complexity maintaining currency vendor dependence frequent upgrade/replacement cycles

- single user database: supports only one user at a time. - desktop database: a single user database that runs on a personal computer - multi-user database: supports multiple users at one time. - work-group database: a multi-user database that supports a small number of users (50 or less) - enterprise database: a multi-user database that supports a large number of users (50+) - centralized database: supports data located at a single site. - distributed database: supports data distributed across several different sites - operational/transactional/production database: for day-to-day operations - data warehouse: stores data used to generate info required to make tactical or strategic decisions

hardware software people procedures data

data about data, through which the end user data are integrated and managed.

a poorly designed database may produce difficult to trace errors that result in bad decision making -- and bad decision making can lead to the failure of an organization.

- sophisticated hardware and software, trained personnel - training, licensingm and regulation compliance costs - vendor dependence - vendors are less likely to offer pricing point advantages to existing customers - updating of hardware and software; additional training

unstructured data is simply data that has not been processed to yield information. examples of both types would include: An invoice. If one were to take an invoice and simply scan it into a graphic, it would be unstructured data. In contrast, if it were processed and put into a database (subsequently becoming structured data), employees could eventually find the monthly averages, amount owed, etc. from various invoices. While both are prevalent, I would think semi-structured data would be the most common in a typical business. Some data is stored but not processed (unstructured data such as memos), and some others are stored in databases (such as invoices) but most data are only processed to a certain extent that is displayed in a prearranged format but not able to yield all of the information contained within.

spreadsheets do not support basic functionality such as: support for self-documentation through metadata enforcement of data types or domains to ensure consistency of data within a column, defined relationships among tables, or contraints to ensure consistency of data across related tables.

Common problems with using both a collection of spreadsheets created by end users and the typical file system include: lengthy development times difficulty of getting quick answers complex system administration lack of security and limited data sharing extensive programming

The loss of direct, hands on access to business data to end-users was significant because it gave them the tools to convert their data into the information they needed and manipulating the company data that would allow them to create new information. However, it seperated end-users from data. While this increased security, prevented redundancy and the such, it also created a delay in which the end-user could request information from the data and when it was delivered by the DP.

Because you are outsourcing your data to a entity with large database assets, thus lowering costs. Also you eliminate costs in hardware and software required to maintain your own database.