Contains the full lesson along with a supporting toolkit, including teachers’ notes.
In today's world easy access to information is the life blood of commercial organisations. Financial data, human resourcesrecords, customer data, product inventories, form the backdrop to operational and strategic decisions. Misinformation can destroy companies, as happened with a multi-national company operating in Dublin in the 1970s when its manufacturing output was mistakenly based on sales to depots around the world rather than to customers. Modern computer systems make a repetition of this kind of error unlikely. Today the amount of data stored by an organisation can be enormous; the Ordnance Survey of Ireland (OSI), based in the Phoenix Park, holds more than 220 terabytes of data ‐ possibly the largest database in Ireland. This lesson covers the basics of this technology, its origins, the types of database, the concepts of database management, database security, data transaction security and database design.
What is a Database?
A database is a computerised store of information (collection of data in digital form) organised so as to allow efficient access to the information for some defined purpose. For instance, a database might hold inventory information to allow stocktaking, identification of re-order levels, analysis of high usage items, etc. It is inextricably linked with (though distinct from) a database management system (DBMS), which is the software system that manages the efficient access to the database.
In the early days of computing data was stored on punched cards, and later on tape. These were not easily accessible; reading and writing were very slow and cumbersome operations by modern standards. Like an audio or video tape, a computer tape needs to be wound and rewound to read a specific piece of information. However, the introduction of magnetic discs and drums in the mid 1960s allowed direct access to specific information locations; this innovation facilitated the development of electronic databases.