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21 lines
836 B
Markdown
21 lines
836 B
Markdown
---
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title: "09-data-modelling-and-normalisation"
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tags:
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- info201
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- lecture
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sr-due: 2022-06-18
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sr-interval: 31
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sr-ease: 250
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---
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- [redundancy-and-anomalies](notes/redundancy-and-anomalies.md)
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- [dependencies](notes/dependencies.md)
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wia functional dependecy::when some attribute has exactly one associated other attribute
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wia transitive dependency:: A→B, B→C [Transitive dependency](notes/dependencies.md#Transitive%20dependency) <!--SR:!2022-5-521,3,250-->
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wia partial dependency:: when a subset of the left determines the right<!--SR:!2022-5-521,3,250-->
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wia multivalued dependency::when something has a set of associated values of another attribute
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- [normalisation](notes/normalisation.md)
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what is normalisation::formal process of eliminanting unnecessary redundancy in relations by splitting relations into smaller chunks |