terjesb

(use '[datomic.api :only [db q] :as d])

;;not supplied:
;;* connecting to a db named "conn" 
;;      (checkout awesome Jonas Edlunds gist 
;;       for inspiration: https://gist.github.com/3122363 )
;;* a schema that fit's the following person-datoms

;; Problem:
;;it's a bit quirky to generate references by functions to transact them to datoms

terjesb

(use '[datomic.api :only [q db] :as d])

(def uri "datomic:mem://accounts")

;; create database
(d/create-database uri)

;; connect to database
(def conn (d/connect uri))

terjesb

;; Datomic example code
(use '[datomic.api :only (db q) :as d])

;; ?answer binds a scalar
(q '[:find ?answer :in ?answer]
   42)

;; of course you can bind more than one of anything
(q '[:find ?last ?first :in ?last ?first]
   "Doe" "John")

terjesb

;; Datomic example code

;; demonstrates various update scenarios, using a news database
;; that contains stories, users, and upvotes

;; grab an in memory database
(use '[datomic.api :only (q db) :as d])

(def uri "datomic:mem://foo")

terjesb

(ns logicrels.fred
  (:require [clojure.xml :as xml]
            [clojure.core.logic :as logic]))

;; (config :fred-key (do "See http://api.stlouisfed.org/api_key.html" nil))

;; (clojure.pprint/pprint (sort-by :date (fred-test "DGS10" "2012-07-02")))

;; ({:target "1.61", :date "2012-05-31", :value "1.59"}
;;  {:target "1.61", :date "2012-06-01", :value "1.47"}

terjesb

(ns lucenalog.core
    "Lucenalog = Datalog interface to Lucene in 10 lines.

Simple but powerful.

Use

  (db/add (index) {:a \"foo\" :b \"bar\"})

to index a map with Lucene.  Then you can use the relation

terjesb

(use '[datomic.api :only [db q] :as d])

(def schema
  [{:db/id #db/id[:db.part/db]
    :db/ident :num
    :db/valueType :db.type/long
    :db/cardinality :db.cardinality/one
    :db.install/_attribute :db.part/db}

   {:db/id #db/id[:db.part/db]

terjesb

;; Datomic example code
;; Demonstrates using datalog with Clojure defrecords
(use '[datomic.api :only [q db] :as d])

;;; http://www.lshift.net/blog/2010/08/21/some-relational-algebra-with-datatypes-in-clojure-12
(defrecord Supplier [number name status city])
(defrecord Part [number name colour weight city])
(defrecord Shipment [supplier part quantity])

;; sample data

terjesb

;; The Datomic schema is made up of Datomic data, so you manipulate it
;; with ordinary queries and transactions -- and with ordinary code
;; in Java or Clojure.

;; query rule that finds attributes in schema whose names start with ?prefix
;; note the Java interop call to .startsWith
;; you could create a similar rule for namespace prefixes
(def rules '[[[attr-starts-with ?prefix ?attr]
              [?e :db/valueType]
              [?e :db/ident ?attr]

terjesb

;; Datomic sample code
;; schema query for attribute types in specified namespaces

(q '[:find ?attr
     :in $ [?include-ns ...]                ;; bind ?include-ns once for each item in collection
     :where
     [?e :db/valueType]                     ;; all schema types (must have a valueType)
     [?e :db/ident ?attr]                   ;; schema type name
     [(datomic.Util/namespace ?attr) ?ns]   ;; namespace of name
     [(= ?ns ?include-ns)]]                 ;; must match one of the ?include-ns