Databases


Introduction

Databases lie at the heart of most IT systems whether in businesses, organizations or other institutions.Databases enable organizations to maintain accurate and comprehensive records. In order to appreciate therole that databases play, the ITGS student must have an understanding of how they work, which can only be gained from the design and creation of basic relational databases as well as by examining how databases are used in specified scenarios (for instance, schools, retail stores, online shopping, online reservations).The increasing use of databases raises a range of social impacts and ethical issues such as the rights ofindividuals with respect to the storage and potential sale of their personal data or the ease of data miningand data matching. Students are expected to discuss these issues and, where appropriate, evaluate possiblesolutions.
Possible scenario
A vet requires information about pet owners and their pets. The ITGS student must be able to develop an
original IT solution to meet the vet’s needs. This knowledge should be acquired through a practical activity
where the student creates a (minimum) three-table relational database (first normal form only) that uses
queries to interrogate the data, forms to enable the easy input printed information as required.

WHAT IS A DATABASE?
A database consists of an organized collection of data for one or more uses, typically in digital form. One way of classifying databases involves the type of their contents, for example: bibliographic, document-text, statistical. Digital databases are managed using database management systems, which store database contents, allowing data creation and maintenance, and search and other access.

IT concepts to address in this topic
Database organization
Table
Field, data types, key field/primary key, secondary key
Record
Flat-file database, relational database, normalization
Database management system
Specialized databases: for example, web databases, online encyclopedias

Functions
Data validation: data types, range check, check digit, field size, input mask, drop-down list
Queries: for example, searching, sorting, filtering, use of Boolean operators (AND, NOT, OR)
Data entry form
Report generation
Macros
Transfer of data between databases and other applications

Data storage and accessData integrity, reliability, redundancy
Data matching, data mining
Database security

Practical database techniques (see above for definition)
Table
Field, data types, key field/primary key, secondary key
Record
Linking tables to create a relational database
Data maintenance: changing, editing, deleting records
Queries: for example, searching, sorting, filtering, use of Boolean operators (AND, NOT, OR)
Data entry form
Report generation
Creating and editing simple macros
Mail merge


Social and ethical issues related to information systems and databases

  • acknowledgment of data sources - RELIABILITY
  • the freedom of information act - PRIVACY
  • privacy principles - PRIVACY
  • accuracy of data and the reliability of data sources - ACCURACY and RELIABILITY
  • access to data, ownership and control of data - AUTHORIZATION and AUTHENTICATION
  • new trends in the organisation, processing, storage and retrieval of data such as data warehousing and data-mining -DIGITAL DIVIDE
Articles related to Databases



Simple tutorial using Access 2007









Data mining in shopping malls