> ## Documentation Index
> Fetch the complete documentation index at: https://docs.a1facts.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# KnowledgeGraph

> The `KnowledgeGraph` class manages interactions with the graph database.

The `KnowledgeGraph` class is responsible for adding, updating, and querying entities and relationships in the graph database, based on a provided ontology.

### `__init__(self, ontology: KnowledgeOntology, use_neo4j: bool = False)`

Initializes a new instance of the `KnowledgeGraph` class.

<RequestExample>
  ```python theme={null}
  from a1facts.graph import KnowledgeGraph
  from a1facts.ontology import KnowledgeOntology

  ontology = KnowledgeOntology(ontology_file="ontology.yaml")
  kg = KnowledgeGraph(ontology=ontology, use_neo4j=False)
  ```
</RequestExample>

**Parameters:**

* `ontology` (KnowledgeOntology): The ontology defining the graph's structure.
* `use_neo4j` (bool, optional): Whether to use Neo4j as the backend. Defaults to `False`.

### `query(self, query: str)`

Executes a natural language query against the knowledge graph.

<RequestExample>
  ```python theme={null}
  result = kg.query("what do you know about how UnitedHealth competes with CVS?")
  print(result)
  ```
</RequestExample>

**Parameters:**

* `query` (str): The natural language query to execute.

**Returns:**

* The content of the agent's response as a string.

### `update_knowledge(self, knowledge: str)`

Updates the knowledge graph with new, unstructured information.

<RequestExample>
  ```python theme={null}
  knowledge_to_add = "UnitedHealth Group is a diversified health and well-being company."
  result = kg.update_knowledge(knowledge_to_add)
  print(result)
  ```
</RequestExample>

**Parameters:**

* `knowledge` (str): A string of unstructured knowledge to add to the graph.

**Returns:**

* The content of the agent's response as a string.

### `close(self)`

Closes the connection to the graph database.

<RequestExample>
  ```python theme={null}
  kg.close()
  ```
</RequestExample>