About

ClaraEAV is a thin layer over Clara-Rules API that simplifies working with EAV triplets, similar to Triplestores.

The main benefit of EAV triplets over Clara's default n-tuples (arbitrary records) is that updates (equivalent to a retraction and an insertion) are local to the attribute (EAV triplet). Updating an n-tuple requires retraction and re-insertion of the whole tuple. The downside is extra joins are needed to build back an entity from it's constituent EAVs.

Installation

ClaraEAV releases are on Clojars:

Usage

You should be familiar with Clara Rules before using ClaraEAV. See the documentation on Cljdoc:

(ns sample
  (:require [clara.rules :as r]
            [clara-eav.rules :as er]))

(er/defquery todo-q [:?e] 
  [?todo <- er/entity :from [[?e]]])

(er/defsession session 
  'sample)

(def tx
  #:todo{:db/id :new
         :text "..."
         :done false})

(-> session
    (er/upsert tx)
    (r/fire-rules)
    (r/query todo-q :?e :new))

; ({:?e :new, :?todo #:todo{:db/id :new, :text "...", :done false}})

Credits

• Clara Rules the library this is built on
• Precept the origin of all ideas
• FactUI DSL parsing ideas