Flashcards
Topic 6
Flashcards do conjunto (9)
- 1NormalisationA mathematical technique for analysing data and is a staged process which improves the database design at each stage. At this level we need to look at normalisation as a three stage process called 1st normal form, 2nd normal form and 3rd normal form.
- 2Data redundancyRefers to the uneccessary duplication of data. A company may hold its data in different files. This is wasteful beacuse some data may need to be inputted twice.
- 3Data consistencyThe same data has exactly the same value and formatting throughout the system. By using one file to hold a central pool of data this means if information is changed in one file it does not need to be changed in another.
- 4Data integrityThe correctness i.e. the extent to which it turthfully represents original information.
- 5Data independenceThe data and the applications/programs used to access it are seperate.
- 6Database securityHirearchy of passwords - limits users to various parts of the program. A receptionist would only have access to basic patient details whilst a doctor would see all infomration on the patient.
- 7Database securityAccess rights - to parts of the program only certain users can access and change data. A nurse would see all the information on a patient but be unable to alter the drug dose details whilst a doctor could.
- 8Database securityStorage of data seperate from the programs - this means that the data is not stored with the program that it is using. The data is shielded by the database management system which determines what data the program is allowed to see.
- 9Data warehouseis a larger database used to store a organisations historical data which is used by a Management Information System (MIC) to extract information
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- FlashCards sobre Topic 6, criado por samantha routledge em 17-10-2017.
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- samantha routledge
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