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copied!<p>You can't directly persist multi-dimensional lists/vectors but you can use a linking entity to accomplish something similar:</p> <pre><code>;; sample attributes [{:db/id #db/id[:db.part/db] :db/ident :some/ref-value :db/valueType :db.type/ref :db/isComponent true :db/cardinality :db.cardinality/many :db.install/_attribute :db.part/db} {:db/id #db/id[:db.part/db] :db/ident :some/list-value :db/valueType :db.type/string :db/cardinality :db.cardinality/many :db.install/_attribute :db.part/db}] ;; [["a" "b" "c"]["d" "e" "f"]] [{:db/id #db/id[:db.part/user -1] :some/list-value ["a" "b" "c"]} {:db/id #db/id[:db.part/user -2] :some/list-value ["d" "e" "f"]} {:db/id #db/id[:db.part/user] :some/ref-value [#db/id[:db.part/user -1] #db/id[:db.part/user -2]]}] </code></pre> <p>Note that you can use negative numbers to link entities together. They will be replaced by real entity ids when you transact them.</p> <p><strong>EDIT</strong>: Starting with version 0.8.4020, Datomic supports nested <a href="http://blog.datomic.com/2013/06/component-entities.html" rel="noreferrer">component entities</a> (containment relationships specified by <code>:db/isComponent</code>) as part of the transaction data. e.g.</p> <pre><code> ;; [["a" "b" "c"]["d" "e" "f"]] [{:db/id #db/id[:db.part/db] :some/ref-value [{:some/list-value ["a" "b" "c"]} {:some/list-value ["d" "e" "f"]}]}] </code></pre> <p>The nested maps expand into two sub-entities, both created in the same partition as the container/parent entity. For a full code sample, see <a href="https://gist.github.com/a2ndrade/5820364" rel="noreferrer">https://gist.github.com/a2ndrade/5820364</a></p>

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