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The prerequisite relationship between Knowledge Nodes is symbolized by Knowledge Edges. Knowledge Edges are the last objects to instantiate while setting up your knowledge’s structure on our API.\\ {{:api2:knowledge_structure:graph.jpg?400|graph}} ===Object resources=== ^ Property ^ Type ^ Description ^ | knowledge_graph_id | Integer | The knowledge graph the knowledge edge belongs to | | source_node_id | Integer | The source node of the knowledge edge | | destination_node_id | Integer | The destination node of the knowledge edge | ===Create (POST)=== ^ Method | POST | ^ URL | /knowledge_edges | ==Parameters (*Requiered parameters)== ^ Property ^ Type ^ Description ^ | knowledge_graph_id* | Integer | The knowledge graph the knowledge edge belongs to | | source_node_id* | Integer | The source node of the knowledge edge | | destination_node_id* | Integer | The destination node of the knowledge edge | ==Send the request (JSON input example)== <code> { knowledge_graph_id: 1, source_node_id: 1, destination_node_id: 2 } </code> ==Get the response (JSON output example)== <code> { id: 1, knowledge_graph_id: 1, source_node_id: 1, destination_node_id: 2 } </code> ===Fetch (GET)=== ^ Method | GET| ^ URL | /knowledge_edges/{knowledge_edge_id} | If no knowledge_edge_id is provided it will fetch all the Knowledge Edges for your instance. ==Get the response (JSON output example)== **With ID provided**\\ <code> { id: 1, knowledge_graph_id: 1, source_node_id: 1, destination_node_id: 2 } </code> **Without ID provided**\\ <code> [ { id: 1, knowledge_graph_id: 1, source_node_id: 1, destination_node_id: 2 }, { id: 2, knowledge_graph_id: 1, source_node_id: 1, destination_node_id: 3 } ] </code> ===Fetch Knowledge Edges by Knowledge Node (GET)=== You can get all related Knowledge Edges for a given Source Knowledge Node\\ ^ Method | GET | ^ URL | /knowledge_nodes/{knowledge_node_id}/knowledge_edges |