datomic-time.clj

(let [dt  #(-> (clj-time.core/date-time 2015 % %2)
               clj-time.coerce/to-date)
      now (d/db (d/connect (db/database-uri :main)))]
  [(db/conn (db/database-uri :main))
   (vec
    (for [db [now ;; 29th July 2015
              (-> now
                  (d/since (dt 2 1))) ;; 1st Feb 2015
              (-> now
                  (d/as-of (dt 2 1))) ;; 1st Feb 2015
              (-> now
                  (d/since (dt 2 1))      ;; 1st Feb 2015
                  (d/as-of (dt 4 1)))]]   ;; 1st April 2015
      [db
       (->> db d/basis-t)
       (->> db d/next-t)
       (->> db d/basis-t d/t->tx)
       (->> db d/basis-t d/t->tx (d/entity db) d/touch)]))])

[#<Connection
 {:db-id                "db-50d3055e-99fc-4639-835c-16c5e88890f7"
  :index-rev            625
  :basis-t              25630814
  :next-t               25630816
  :unsent-updates-queue 0
  :pending-txes         0}>

 ;; I thought i would see different :basis-tx, :next-t, :t->tx, and
 ;; entities for each of these cases.

 [{:db             datomic.db.Db@8f42a8dd
   :basis-t        25630814
   :next-t         25630816
   :t->tx          13194165164126
   :touched-entity
   {:db/txInstant  #inst "2015-07-29T08:45:22.093-00:00"
    :db/id         13194165164126}}
  {:db             datomic.db.Db@8e6794f5
   :basis-t        25630814
   :next-t         25630816
   :t->tx          13194165164126
   :touched-entity
   {:db/txInstant  #inst "2015-07-29T08:45:22.093-00:00"
    :db/id         13194165164126}}
  {:db             datomic.db.Db@8e1d54f5
   :basis-t        25630814
   :next-t         25630816
   :t->tx          13194165164126
   :touched-entity {:db/id 13194165164126}}
  {:db             datomic.db.Db@8d2bde09
   :basis-t        25630814
   :next-t         25630816
   :t->tx          13194165164126
   :touched-entity {:db/id 13194165164126}}]]

(let [now (db/db)
      f   (fn [t]
            (when t
              [t (d/t->tx t) (d/touch (d/entity now (d/t->tx t)))]))]
  (for [db [now ;; 29th July 2015
            (-> now
                (d/since #inst "2015-02-01")) ;; 1st Feb 2015
            (-> now
                (d/as-of #inst "2015-02-01")) ;; 1st Feb 2015
            (-> now
                (d/since #inst "2015-02-01")      ;; 1st Feb 2015
                (d/as-of #inst "2015-04-01"))]]   ;; 1st April 2015
    { :basis  (f (d/basis-t db))
      :next   (f (d/next-t db))
      :as-of  (f (d/as-of-t db)) 
      :since  (f (d/since-t db))
      }))

{:basis [25642501 13194165175813 {:db/id 13194165175813
                                  :db/txInstant #inst "2015-07-28T20:24:07.403-00:00"}]
 :next [25642504 13194165175816 {:db/id 13194165175816}]
 :as-of nil
 :since nil} 

{:basis [25642501 13194165175813 {:db/id 13194165175813
                                  :db/txInstant #inst "2015-07-28T20:24:07.403-00:00"}]
 :next [25642504 13194165175816 {:db/id 13194165175816}]
 :as-of nil
 :since [19229736 13194158763048 {:db/id 13194158763048
                                  :db/txInstant #inst "2015-01-31T22:30:08.353-00:00"}]} 

{:basis [25642501 13194165175813 {:db/id 13194165175813
                                  :db/txInstant #inst "2015-07-28T20:24:07.403-00:00"}]
 :next [25642504 13194165175816 {:db/id 13194165175816}]
 :as-of [19229736 13194158763048 {:db/id 13194158763048
                                  :db/txInstant #inst "2015-01-31T22:30:08.353-00:00"}]
 :since nil} 

{:basis [25642501 13194165175813 {:db/id 13194165175813
                                  :db/txInstant #inst "2015-07-28T20:24:07.403-00:00"}]
 :next [25642504 13194165175816 {:db/id 13194165175816}]
 :as-of [21809460 13194161342772 {:db/id 13194161342772
                                  :db/txInstant #inst "2015-03-31T23:55:05.636-00:00"}]
 :since [19229736 13194158763048 {:db/id 13194158763048
                                  :db/txInstant #inst "2015-01-31T22:30:08.353-00:00"}]}