RosettaCodeData/Task/Hash-join/Clojure/hash-join.clj

21 lines
616 B
Clojure

(defn hash-join [table1 col1 table2 col2]
(let [hashed (group-by col1 table1)]
(flatten
(for [r table2]
(for [s (hashed (col2 r))]
(merge s r))))))
(def s '({:age 27 :name "Jonah"}
{:age 18 :name "Alan"}
{:age 28 :name "Glory"}
{:age 18 :name "Popeye"}
{:age 28 :name "Alan"}))
(def r '({:nemesis "Whales" :name "Jonah"}
{:nemesis "Spiders" :name "Jonah"}
{:nemesis "Ghosts" :name "Alan"}
{:nemesis "Zombies" :name "Alan"}
{:nemesis "Buffy" :name "Glory"}))
(pprint (sort-by :name (hash-join s :name r :name)))