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−
+
−Metadata
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−--------
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−
+
−.. index::
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−   schema: meta-data;
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−   schema: eid; creation_date; modification_data; cwuri
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−   schema: created_by; owned_by; is; is_instance;
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−
+
−Each entity type in |cubicweb| has at least the following meta-data attributes and relations:
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−
+
−`eid`
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−  entity's identifier which is unique in an instance. We usually call this identifier `eid` for historical reason.
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−
+
−`creation_date`
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−  Date and time of the creation of the entity.
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−
+
−`modification_date`
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−  Date and time of the latest modification of an entity.
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−
+
−`cwuri`
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−  Reference URL of the entity, which is not expected to change.
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−
+
−`created_by`
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−  Relation to the :ref:`users <CWUser>` who has created the entity
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−
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−`owned_by`
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−  Relation to :ref:`users <CWUser>` whom the entity belongs; usually the creator but not
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−  necessary, and it could have multiple owners notably for permission control
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−
+
−`is`
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−  Relation to the :ref:`entity type <CWEType>` of which type the entity is.
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−
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−`is_instance`
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−  Relation to the :ref:`entity types <CWEType>` of which type the
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−  entity is an instance of.
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−