:lookup does not work with :unique indexes.

[wotbrew]

With :hash

(let [db {:A [{:id 1 :x 1} {:id 2 :x 1} {:id 3 :x 2}]}
      idx [[:from :A] [:hash :id]]
      db (mat db idx)]
  (q db [[:lookup idx 1]]))
=> ({:id 1, :x 1})

With :unique

(let [db {:A [{:id 1 :x 1} {:id 2 :x 1} {:id 3 :x 2}]}
      idx [[:from :A] [:unique :id]]
      db (mat db idx)]
  (q db [[:lookup idx 1]]))
=> ([:id 1] [:x 1])

Failing test and fix please :)

[wotbrew]

Make sense, the lookup fn needs to somehow be specialised for :unique as it maps to single rows, rather than sets (like btree, hash).