1 

     2 Meta-data

     3 ---------

     4 

     5 .. index::

     6    schema: meta-data;

     7    schema: eid; creation_date; modification_data; cwuri

     8    schema: created_by; owned_by; is; is_instance;

     9 

    10 Each entity type in |cubicweb| has at least the following meta-data attributes and relations:

    11 

    12 eid

    13   entity's identifier which is unique in an instance. We usually call this identifier `eid` for historical reason.

    14 

    15 creation_date

    16   Date and time of the creation of the entity.

    17 

    18 modification_date

    19   Date and time of the latest modification of an entity.

    20 

    21 cwuri

    22   Reference URL of the entity, which is not expected to change.

    23 

    24 created_by

    25   Relation to the :ref:`users <CWUser>` who has created the entity

    26 

    27 owned_by

    28   Relation to :ref:`users <CWUser>` whom the entity belongs; usually the creator but not

    29   necessary, and it could have multiple owners notably for permission control

    30 

    31 is

    32   Relation to the :ref:`entity type <CWEType>` of which type the entity is.

    33 

    34 is_instance

    35   Relation to the :ref:`entity types <CWEType>` of which type the

    36   entity is an instance of.

    37 

    38 

    39 Virtual RQL relations

    40 ---------------------

    41 XXX move this to the RQL chapter.

    42 

    43 Those relations may only be used in RQL query and are not actual attributes of your entities...

    44 

    45 has_text

    46   Relation to use to query the full text index (only for entities having fulltextindexed attributes).

    47 

    48 identity

    49   Relation to use to tell that a RQL variable should be the same as entity another

    50   (but you've to use two different rql variables for querying purpose)

    51 

    52 

    53 

    54 .. |cubicweb| replace:: *CubicWeb*