17 lines
578 B
Markdown
17 lines
578 B
Markdown
### [Relational Algebra - Recap](obsidian://open?vault=Computer%20Science%20Year%201&file=Semester%201%2FDatabase%20Systems%2FWeek%2010%2FWeek%2010)
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- High level & procedural
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- Defines how to build relations
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#### Data Manipulation Language
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- Provides set of operations
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- Data retrieval - query language
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- ex. SQL
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#### Closure
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- Operations work on one or more relations to define another relation without changing the original
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- Both operands and results are relations, output from one operation can become the input for another operation.
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- This allows nested expressions.
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