19 lines
599 B
Markdown
19 lines
599 B
Markdown
# lec13
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## Lab Exercises
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This lecture has a lab portion in `lab/` directory.
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Directions are on `index-structures-lab.pdf` and `ordered-indexes-lab.pdf`.
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## Indexing
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We create an index based on some field, where we sort the entries in this index table.
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Each entry then contains a pointer to each record in the target table.
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Sorting the indexes allows us to search them _much faster_ than we could ever do on disk.
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> What about collision?
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Then we simply add a pointer to the index's list of associated pointers.
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It's important to note that indexes are tables, just like everything else in sql.
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