Business computing Session 9 Databases

Office suite softwares (1) Word processor : Word, it is a presentation software, and a letter and document preparation software. The main orientation is DISPLAY Presentation software : PowerPoint, it is also a presentation software, to make slides to support a speech

Office suite softwares (2) Spreadsheet : Excel, it is a software to make calculations on data, particularly on data coming in the form of tables It is perfectly suited for financial project data (usually columns correspond to years) It is also a presentation software, and it has graphic capabilities

Office suite softwares (3) Database : Access A database is a software to store, treat and display ORGANIZED information What is organized information ? It is information with a repetitive pattern (also called structure)

An example A football player card collection. What data shall we enter for each player ? Zidane, Reccoba, Raul Lastname : Zidane, Reccoba, Raul Firstname : Zinedine, Alvaro, Gonzalez Team : Real Madrid, Inter Milan, Real Madrid Birthdate : 1972, 1974, 1976 Position in the field : middle attack, middle attack, attack Nationality : French, Uruguay, Spaniard

Example of data with a repetitive structure : a football player card collection In a football player card collection we enter on each card : The lastname (for instance : Zidane, or Ronaldo) The firstname (for instance : Zinedine) The club (Real Madrid, Real Madrid) The birthdate (1972, in Marseille, 1976) The picture Position in the field

Shoeboxes and Databases A database is the electronic version of a shoebox with cardboard cards On each card there is information, with the same structure, on an item, or a person The structured information on each card is contained in FIELDS In each field there is elementary information The information contained in the field « birthdate » for the record of Raul is : 1976

Terminology The equivalent of a card is called a RECORD The containers for elementary information on a record are called FIELDS For example, the content of the field « club » on the record for Michael Owen is Liverpool FC The collection of records is called a TABLE

A football player database We first of all construct the structure of the table Then we enter data in the table Finally we display data using a form (Note we can also enter new data, and correct data in the form mode)

The need for other tables In our football player db we will have say 1000 players, and say 50 clubs If for each club we have some information : coach, stadium, turnover, it will be a source of mistake to type again all this information for 20 or 30 players That’s where we create secondary tables : we will create a table for the clubs