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16 lines
337 B
Markdown
16 lines
337 B
Markdown
# Dictionaries
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`A dictionary` is a mapping (key `->` attributes) that can be used in a query as functions.
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You can think of this as a more convenient and efficient type of JOIN with dimension tables.
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There are built-in (internal) and add-on (external) dictionaries.
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```eval_rst
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.. toctree::
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external_dicts
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internal_dicts
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```
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