rename issue - renaming more than one columns

[gowda]

(-> (project items [:content :id :user_id]) (join users (where (= :items.user_id :users.id))) (rename {:items.id :idx}))

generates

SELECT items.content,items.id,items.user_id,users.* FROM items AS items(content,idx,user_idx) JOIN users ON (items.user_id = users.id)

this sql query renames two columns for 'items' table, 'id' and 'user_id'. the intent is to rename only one column 'id' to 'idx'.