langchain_community.graphs.ontotext_graphdb_graph
.OntotextGraphDBGraph¶
- class langchain_community.graphs.ontotext_graphdb_graph.OntotextGraphDBGraph(query_endpoint: str, query_ontology: Optional[str] = None, local_file: Optional[str] = None, local_file_format: Optional[str] = None)[source]¶
Ontotext GraphDB https://graphdb.ontotext.com/ wrapper for graph operations.
- Security note: Make sure that the database connection uses credentials
that are narrowly-scoped to only include necessary permissions. Failure to do so may result in data corruption or loss, since the calling code may attempt commands that would result in deletion, mutation of data if appropriately prompted or reading sensitive data if such data is present in the database. The best way to guard against such negative outcomes is to (as appropriate) limit the permissions granted to the credentials used with this tool.
See https://python.langchain.com/docs/security for more information.
Set up the GraphDB wrapper
- Parameters
query_endpoint (str) – SPARQL endpoint for queries, read access
query_ontology (Optional[str]) –
local_file (Optional[str]) –
local_file_format (Optional[str]) –
If GraphDB is secured, set the environment variables ‘GRAPHDB_USERNAME’ and ‘GRAPHDB_PASSWORD’.
- Parameters
query_ontology (Optional[str]) – a CONSTRUCT query that is executed
query_endpoint (str) –
local_file (Optional[str]) –
local_file_format (Optional[str]) –
on the SPARQL endpoint and returns the KG schema statements Example: ‘CONSTRUCT {?s ?p ?o} FROM <https://example.com/ontology/> WHERE {?s ?p ?o}’ Currently, DESCRIBE queries like ‘PREFIX onto: <https://example.com/ontology/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> DESCRIBE ?term WHERE {
?term rdfs:isDefinedBy onto:
}’ are not supported, because DESCRIBE returns the Symmetric Concise Bounded Description (SCBD), i.e. also the incoming class links. In case of large graphs with a million of instances, this is not efficient. Check https://github.com/eclipse-rdf4j/rdf4j/issues/4857
- Parameters
local_file (Optional[str]) – a local RDF ontology file.
query_endpoint (str) –
query_ontology (Optional[str]) –
local_file_format (Optional[str]) –
Supported RDF formats: Turtle, RDF/XML, JSON-LD, N-Triples, Notation-3, Trig, Trix, N-Quads. If the rdf format can’t be determined from the file extension, pass explicitly the rdf format in local_file_format param.
- Parameters
local_file_format (Optional[str]) – Used if the rdf format can’t be determined
query_endpoint (str) –
query_ontology (Optional[str]) –
local_file (Optional[str]) –
from the local file extension. One of “json-ld”, “xml”, “n3”, “turtle”, “nt”, “trig”, “nquads”, “trix”
Either query_ontology or local_file should be passed.
Attributes
get_schema
Returns the schema of the graph database in turtle format
Methods
__init__
(query_endpoint[, query_ontology, ...])Set up the GraphDB wrapper
query
(query)Query the graph.
- __init__(query_endpoint: str, query_ontology: Optional[str] = None, local_file: Optional[str] = None, local_file_format: Optional[str] = None) None [source]¶
Set up the GraphDB wrapper
- Parameters
query_endpoint (str) – SPARQL endpoint for queries, read access
query_ontology (Optional[str]) –
local_file (Optional[str]) –
local_file_format (Optional[str]) –
- Return type
None
If GraphDB is secured, set the environment variables ‘GRAPHDB_USERNAME’ and ‘GRAPHDB_PASSWORD’.
- Parameters
query_ontology (Optional[str]) – a CONSTRUCT query that is executed
query_endpoint (str) –
local_file (Optional[str]) –
local_file_format (Optional[str]) –
- Return type
None
on the SPARQL endpoint and returns the KG schema statements Example: ‘CONSTRUCT {?s ?p ?o} FROM <https://example.com/ontology/> WHERE {?s ?p ?o}’ Currently, DESCRIBE queries like ‘PREFIX onto: <https://example.com/ontology/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> DESCRIBE ?term WHERE {
?term rdfs:isDefinedBy onto:
}’ are not supported, because DESCRIBE returns the Symmetric Concise Bounded Description (SCBD), i.e. also the incoming class links. In case of large graphs with a million of instances, this is not efficient. Check https://github.com/eclipse-rdf4j/rdf4j/issues/4857
- Parameters
local_file (Optional[str]) – a local RDF ontology file.
query_endpoint (str) –
query_ontology (Optional[str]) –
local_file_format (Optional[str]) –
- Return type
None
Supported RDF formats: Turtle, RDF/XML, JSON-LD, N-Triples, Notation-3, Trig, Trix, N-Quads. If the rdf format can’t be determined from the file extension, pass explicitly the rdf format in local_file_format param.
- Parameters
local_file_format (Optional[str]) – Used if the rdf format can’t be determined
query_endpoint (str) –
query_ontology (Optional[str]) –
local_file (Optional[str]) –
- Return type
None
from the local file extension. One of “json-ld”, “xml”, “n3”, “turtle”, “nt”, “trig”, “nquads”, “trix”
Either query_ontology or local_file should be passed.