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Chapter 5
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- 1A database contains tables, records and fields. Using examples from a school, describe the terms tables, records and fieldsA table is a collection of data that all relates to one thing, for example, a table could contain all the information about students in one class at a school. A record is a single row within a table that contains information about a single thing or event, for example, all the information on one student. A field is an individual data item without a record, for example, Exam ID
- 2Identify the characteristics of data in 2NF and 3NFThe data must be atomic
The table must have a primary key
The field names have to be unique
There should be no repeating fields
All of the non-key fields can be found using the entire primary key
All non-key items are fully dependent on the primary key - 3Describe the advantages of normalisationIt removes redundant and duplicate data saving on storage space
It makes the database easier to maintain as the data is not duplicated
It increases integrity
Improves flexibility of the database. If the needs of the organisation change then the database can be adapted without any major changes
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- (Chapter 5 - Relational Database Concepts) ICT AS Fichas sobre Chapter 5, creado por Katie Difford el 12/04/2013.
- Creado por
- Katie Difford · abr 2013
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- 19 feb 2016
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