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Databases Defined. Databases . Defined: a collection of organised data to enable access, retrieval and processing Databases manage data by filtering to select a small set of data, eg. sorting Strengths of Databases: Powerful, efficient access to information Weaknesses of Databases:
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Databases • Defined: a collection of organised data to enable access, retrieval and processing • Databases manage data by filtering to select a small set of data, eg. sorting • Strengths of Databases: • Powerful, efficient access to information • Weaknesses of Databases: • Steep learning curve involved in learning the program
Databases - Structure • Field, combination of characters and is smallest unit of data a user accesses • Field name, uniquely identifies each field • Record, a group of related fields, eg. students name, address, age, etc.
Databases - Structure • Form, allows the input screen to be formatted
Databases - Structure • Report, result of a query in usable information
Databases Structure • Macros, used to automate regular procedures and tasks • Primary key, a field uniquely identifying each record in a file, eg. Student ID no, Tax file no, etc • Flat file database, only contains one table
Databases Structure • Data types: • Text, names, addresses, post codes, telephone numbers, (set to text because not performing calculations • Number or numeric fields, eg. Currency & date & time • Boolean, eg. Yes/No • Object, a document or media file • Data Formats • Having decided on field type chose format, eg. Fixed decimal places,