操作查询结果

records, summary, keys = driver.execute_query(
    "MATCH (a:Person) RETURN a.name AS name, a.age AS age",
    database_="neo4j",
)
for person in records:  (1)
    print(person)
    # person["name"] or person["age"] are also valid

# Some summary information  (2)
print("Query `{query}` returned {records_count} records in {time} ms.".format(
    query=summary.query, records_count=len(records),
    time=summary.result_available_after
))

print(f"Available keys are {keys}")  # ['name', 'age'] (3)

import neo4j

pandas_df = driver.execute_query(
    "UNWIND range(1, 10) AS n RETURN n, n+1 AS m",
    database_="neo4j",
    result_transformer_=neo4j.Result.to_df
)
print(type(pandas_df))  # <class 'pandas.core.frame.DataFrame'>

import pyvis
from neo4j import GraphDatabase
import neo4j


URI = "<URI for Neo4j database>"
AUTH = ("<Username>", "<Password>")


def main():
    with GraphDatabase.driver(URI, auth=AUTH) as driver:
        # Create some friends
        input_list = [("Arthur", "Guinevre"),
                      ("Arthur", "Lancelot"),
                      ("Arthur", "Merlin")]
        driver.execute_query("""
            UNWIND $pairs AS pair
            MERGE (a:Person {name: pair[0]})
            MERGE (a)-[:KNOWS]->(friend:Person {name: pair[1]})
            """, pairs=input_list,
            database_="neo4j",
        )

        # Create a film
        driver.execute_query("""
            MERGE (film:Film {title: $title})
            MERGE (liker:Person {name: $person_name})
            MERGE (liker)-[:LIKES]->(film)
            """, title="Wall-E", person_name="Arthur",
            database_="neo4j",
        )

        # Query to get a graphy result
        graph_result = driver.execute_query("""
            MATCH (a:Person {name: $name})-[r]-(b)
            RETURN a, r, b
            """, name="Arthur",
            result_transformer_=neo4j.Result.graph,
        )

        # Draw graph
        nodes_text_properties = {  # what property to use as text for each node
            "Person": "name",
            "Film": "title",
        }
        visualize_result(graph_result, nodes_text_properties)


def visualize_result(query_graph, nodes_text_properties):
    visual_graph = pyvis.network.Network()

    for node in query_graph.nodes:
        node_label = list(node.labels)[0]
        node_text = node[nodes_text_properties[node_label]]
        visual_graph.add_node(node.element_id, node_text, group=node_label)

    for relationship in query_graph.relationships:
        visual_graph.add_edge(
            relationship.start_node.element_id,
            relationship.end_node.element_id,
            title=relationship.type
        )

    visual_graph.show('network.html', notebook=False)


if __name__ == "__main__":
    main()

# Get a single record (or an exception) and the summary from a result.
def get_single_person(result):
    record = result.single(strict=True)
    summary = result.consume()
    return record, summary


record, summary = driver.execute_query(
    "MERGE (a:Person {name: $name}) RETURN a.name AS name",
    name="Alice",
    database_="neo4j",
    result_transformer_=get_single_person,
)
print("The query `{query}` returned {record} in {time} ms.".format(
      query=summary.query, record=record, time=summary.result_available_after))

# Get exactly 5 records, or an exception.
def exactly_5(result):
    records = result.fetch(5)

    if len(records) != 5:
        raise Exception(f"Expected exactly 5 records, found only {len(records)}.")
    if result.peek():
        raise Exception("Expected exactly 5 records, found more.")

    return records


records = driver.execute_query("""
    UNWIND ['Alice', 'Bob', 'Laura', 'John', 'Patricia'] AS name
    MERGE (a:Person {name: name}) RETURN a.name AS name
    """, database_="neo4j",
    result_transformer_=exactly_5,
)