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benkamphaus/membership.clj

Created October 26, 2015 23:20
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  1. benkamphaus created this gist Oct 26, 2015.
    69 changes: 69 additions & 0 deletions membership.clj
    View file
    Original file line number Diff line number Diff line change
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    (ns datomic-manual-tests.membership
    (:require [datomic.api :as d]))

    (def db-uri "datomic:mem://memership")
    (d/create-database db-uri)
    (def conn (d/connect db-uri))

    (def schema
    [{:db/id (d/tempid :db.part/db)
    :db/ident :person/name
    :db/valueType :db.type/string
    :db/cardinality :db.cardinality/one
    :db/unique :db.unique/identity
    :db.install/_attribute :db.part/db}
    {:db/id (d/tempid :db.part/db)
    :db/ident :person/membership
    :db/valueType :db.type/ref
    :db/cardinality :db.cardinality/many
    :db/isComponent true
    :db.install/_attribute :db.part/db}
    {:db/id (d/tempid :db.part/db)
    :db/ident :membership/org
    :db/valueType :db.type/ref
    :db/cardinality :db.cardinality/one
    :db.install/_attribute :db.part/db}
    {:db/id (d/tempid :db.part/db)
    :db/ident :membership/role
    :db/valueType :db.type/string
    :db/cardinality :db.cardinality/one
    :db.install/_attribute :db.part/db}
    {:db/id (d/tempid :db.part/db)
    :db/ident :org/name
    :db/valueType :db.type/string
    :db/cardinality :db.cardinality/one
    :db/unique :db.unique/identity
    :db.install/_attribute :db.part/db}])

    @(d/transact conn schema)

    (def init-data
    [{:db/id (d/tempid :db.part/user -1)
    :person/name "Jonas"
    :person/membership [{:db/id (d/tempid :db.part/user -2)
    :membership/org (d/tempid :db.part/user -3)
    :membership/role "President"}]}
    {:db/id (d/tempid :db.part/user -3)
    :org/name "Chess Club"}
    {:db/id (d/tempid :db.part/user -4)
    :person/name "Will"
    :person/membership [{:db/id (d/tempid :db.part/user -5)
    :membership/org (d/tempid :db.part/user -3)
    :membership/role "Underling"}]}])

    @(d/transact conn init-data)

    (let [db (d/db conn)
    pattern '[:person/name
    {:person/membership
    [{:membership/org
    [:org/name
    {:membership/_org
    [{:person/_membership [:person/name]}]}]}]}]]
    (d/pull db pattern [:person/name "Jonas"]))

    ;; Traversing refs from person -> membership -> org -> memberships -> people
    ;{:person/membership [{:membership/org {:membership/_org [{:person/_membership {:person/name "Jonas"}}
    ; {:person/_membership {:person/name "Will"}}]
    ; :org/name "Chess Club"}}]
    ; :person/name "Jonas"}