23 lines
551 B
Text
23 lines
551 B
Text
(defun hash (column table)
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(lists:foldl
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(lambda (x acc)
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(orddict:append (proplists:get_value column x) x acc))
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'()
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table))
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(defun get-hash (col hash-table)
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(proplists:get_value
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(proplists:get_value col r)
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hashed))
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(defun merge (row-1 row-2)
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(orddict:merge
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(lambda (k v1 v2) v2)
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(lists:sort row-1)
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(lists:sort row-2)))
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(defun hash-join (table-1 col-1 table-2 col-2)
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(let ((hashed (hash col-1 table-1)))
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(lc ((<- r table-2))
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(lc ((<- s (get-hash col-2 hashed)))
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(merge r s)))))
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