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Methods

the entity with id = 'src_id' through the relation called 'rel_name'. the entity with id = 'tar_id' through the relation called 'rel_name'.

Method name	Required parameters	Other parameters	Return	Description
get_ent	id	include_content (default value false)	ent	Return the entity with id equal to 'id'
get_ents	oc		ents	Return all entities where their object class equal to 'oc'
get_ents_size	oc		ents_size
get_def	oc		def	Returns a definition by its object class
get_defs			defs	Returns all definitions from the DB
get_src_rels	id, rel_name, tar_oc		src_rels	Returns an array which contains the source relations of the entity with id = 'id'
get_tar_rels	id, rel_name, src_oc		tar_rels	Returns an array which contains the target relations of the entity with id = 'id'
get_atts	id		atts	Returns an array which contains the attributes of the entity with id = 'id'
get_tars_4_src_rel	src_id, rel_name, tar_id	include_content (default value false)	ents	Returns an array entities that has an object class equals to 'tar_oc' and that are related to
get_srcs_4_tar_rel	tar_id, rel_name, src_oc	include_content (default value false)	ents	Returns a array entities that has an object class equals to 'src_oc' and that are related to
exist_rel	src_id, tar_id, rel_name		exist_rel	Returns true, if there is a relation between the entities with ids like: src_id and tar_id.
get_rels	rel_name	src_oc, tar_oc, include_ents	rels	Returns an array of relations, which can be filtered by source and target name, wenn they are not empty. The content of the source and the target of a relation can also be included wenn include_ent is true.
search	query		rs	Returns a json-array (called rs), where each entry is a serie of entities that complies with the pattern (or path parameter).

Description of Data Structures

Basically, the database is composed of three kind of elements: entities, attributes and relation. These elements together form a directed graph. The entity is the central component and represent objects that are characterized by attributes and are connected to others entities by their relations. From the perspective of a entity, there are two kind of relation: source relation and target relations. A relation connects a source and a target. For example, let be Z = {X is_created_by Y} a relation and X and Y two entities. For the entity X, Z is a source relation, because the source of Z is X. In the other hand, For the entity Y, Z is a target relation, because the target of Z is Y.

Now, it will be explained, how the mentioned structures are represented by the json-response:

ent

is a json object that represents the most basic element of the database. An entity will be always returned accompanied by the following sub-json-objects:

id: the identifier of the entity in the DB.
node_type: there are two kind of entities: definitions (node_type='TBox') and concrete entities (node_type='ABox').

These concepts derived from the ontology and means that a entity can be assigned either to an assertion set (Abox) or to a terminological set. A definition describe which kind of attributes and relation can have a concrete entity, in other words a concrete entity is a instance of a definition (like class and object in object-oriented languages).

oc (object class): for a concrete entity, this attribute describes from which definition it derives. Typical object classes of ISMI-DB are: TEXT, WITNESS, PERSON, etc.
ov (own value): the label of the entity.
nov (normalized own value): the normalized version of the own value.
lw (light weight): an entity can or not include its attributes and (sources and target) relations.

If the entity does not contain the mentioned elements, the variable lw is false, in the other case it is true.

If the variable lw, the ent would have also the following objects: