title: In Datomic, how do I get a timeline view of the changes made to the values of a particular entity?
body: <p>I'm following the tutorial, <a href="http://www.datomic.com/company/resources/tutorial">http://www.datomic.com/company/resources/tutorial</a> but I think I am missing a simple piece of the puzzle of how to access Datomic's time model.</p>
  
  <p>If I do a series of adds and retracts</p>
  
  <pre><code>;; DO a series of transactions 
  ;; (transact conn [:db/add entity-id attribute value0])
  
  (use 'datomic.api)
  (dir datomic.api)
  (def conn (connect "datomic:dev://localhost:4334/demo"))
  
  (transact conn '[:db/add 2000 :db/doc "Hello There"])
  (q '[:find ?e ?n :where [?e :db/doc ?n] [(= 2000 ?e)]] (db conn))
  ; =&gt; &lt;HashSet [[2000 "Hello There"]]&gt;
  
  (transact conn '[:db/add 2000 :db/doc "Hello There 1"])
  (q '[:find ?e ?n :where [?e :db/doc ?n] [(= 2000 ?e)]] (db conn))
  ; =&gt; &lt;HashSet [[2000 "Hello There 1"]]&gt;
  
  (transact conn '[:db/add 2000 :db/doc "Hello There 2"])
  (q '[:find ?e ?n :where [?e :db/doc ?n] [(= 2000 ?e)]] (db conn))
  ; =&gt; &lt;HashSet [[2000 "Hello There 2"]]&gt;
  
  (transact conn '[:db/add 2000 :db/doc "Hello There 3"])
  (q '[:find ?e ?n :where [?e :db/doc ?n] [(= 2000 ?e)]] (db conn))
  ; =&gt; &lt;HashSet [[2000 "Hello There 3"]]&gt;
  </code></pre>
  
  <p>How is it possible to get a series of changes of the value on (entity 2000 attribute :db/doc)?</p>
  
  <p>I want to get something in the format of</p>
  
  <pre><code>[ [Transaction Number, Time, Value] .... [Transaction Number, Time, Value]]
  </code></pre>
  
  <p>For example:</p>
  
  <pre><code>[ [T1, "2012-March-16-9:30:12", "Hello There"] 
    .... 
    .... 
    .... 
    [T27, "2012-June-14-9:54:38", "Hello There 3"] ]
  </code></pre>
  
  <p>It can't be that difficult, but there are a lot of :db internal parameters that I'm not familiar with.</p>