BT1005 Managing Information Lecture 3 Introduction to Databases and The Database Approach

Contents File environments –Traditional –Database Data organisation Database Terms

Requirements of Information Information Systems need to provide information that is: –Timely –Accurate –Relevant

Traditional File Environment Data Redundancy and Confusion Program-Data Dependence Lack of Flexibility Lack of Data-Sharing Poor Security

Database Environment “A collection of data organised to serve many applications at the same time, by storing and managing data so that they appear to be in one location” Laudon and Laudon (2000)

Alternative definition “An integrated collection of logically related data items” James O’Brien (2010) “Consolidates many records previously stored in separate files so that a common pool of data serves many applications”

Data Organisation Bit0 or 1 Byte – the letter v FieldBGMarshall-Kalina – a ‘name’ field RecordBGMarshall-Kalina Gr34 SysOps 4668 FileBGMarshall-Kalina Gr34 SysOps 4668 PClare Gr44 SysOps 4670 DWalters Gr33 SysOps 4650 DatabaseLancashire Business School Staff Database

Database Terms Entity Attribute Key field

Database Terms (cont’d) Order Number Order Date Item Number QuantityAmount 56567/10/ Attributes Entity - ORDER Key field Adapted from Laudon and Laudon (2000) Fields

Summary For information to meet organisational needs it must be up-to-date, accurate and quickly available Relational Databases allow this delivery and much more varied information than was previously available