【neo4j】生成关系图 2019-10-04

1. 准备要显示的数据如下

data.csv 文件内容

from,to,amount
A,A,12
A,F,3
A,L,3
A,E,4
B,F,70
B,B,14
B,K,2
B,im,1
B,C,5
D,I,30
D,D,88
D,C,20
Y,G,8
Y,F,132
Y,H,16460
Y,J,8229
Y,emds,2
Y,U,2
Y,V,2
Y,im,20
Y,M,2
W,N,14
W,O,77580
W,L,95
W,C,7
W,P,2
W,Q,1
others,K,219
others,im,28
others,R,222
others,C,59
X,K,10
X,im,35
X,X,83
X,C,45
S,S,8231
S,T,2851
S,L,4323
S,R,8229

2. 使用 python 读取上面的数据，生成 Cypher 语法(以后再升级为直接写数据库)

   from collections import defaultdict
   import pandas as pd

file = r"data.csv"
df = pd.read_csv(file)
node_dict = defaultdict(int)
service_list = list()

row_num = len(df.index)
for i in range(row_num):
    # get the data of each row
    _from, _to, amount = df.loc[i]

    # add the node name to service list if it is new
    # generate the node creation command
    if _from not in service_list:
        command = f"CREATE ({_from}:Node{{name: {repr(_from)}}})"
        print(command)
        service_list.append(_from)
    if _to not in service_list:
        command = f"CREATE ({_to}:Node{{name: {repr(_to)}}})"
        print(command)
        service_list.append(_to)

    # generate relationship creation command
    command = f"CREATE ({_from})-[:Visit{{time:{amount}}}]->({_to})"
    print(command)

生成的 Cypher 语句如下

CREATE (A:Node{name: 'A'})
CREATE (A)-[:Visit{time:12}]->(A)
CREATE (F:Node{name: 'F'})
CREATE (A)-[:Visit{time:3}]->(F)
CREATE (L:Node{name: 'L'})
CREATE (A)-[:Visit{time:3}]->(L)
CREATE (E:Node{name: 'E'})
CREATE (A)-[:Visit{time:4}]->(E)
CREATE (B:Node{name: 'B'})
CREATE (B)-[:Visit{time:70}]->(F)
CREATE (B)-[:Visit{time:14}]->(B)
CREATE (K:Node{name: 'K'})
CREATE (B)-[:Visit{time:2}]->(K)
CREATE (im:Node{name: 'im'})
CREATE (B)-[:Visit{time:1}]->(im)
CREATE (C:Node{name: 'C'})
CREATE (B)-[:Visit{time:5}]->(C)
CREATE (D:Node{name: 'D'})
CREATE (I:Node{name: 'I'})
CREATE (D)-[:Visit{time:30}]->(I)
CREATE (D)-[:Visit{time:88}]->(D)
CREATE (D)-[:Visit{time:20}]->(C)
CREATE (Y:Node{name: 'Y'})
CREATE (G:Node{name: 'G'})
CREATE (Y)-[:Visit{time:8}]->(G)
CREATE (Y)-[:Visit{time:132}]->(F)
CREATE (H:Node{name: 'H'})
CREATE (Y)-[:Visit{time:16460}]->(H)
CREATE (J:Node{name: 'J'})
CREATE (Y)-[:Visit{time:8229}]->(J)
CREATE (emds:Node{name: 'emds'})
CREATE (Y)-[:Visit{time:2}]->(emds)
CREATE (U:Node{name: 'U'})
CREATE (Y)-[:Visit{time:2}]->(U)
CREATE (V:Node{name: 'V'})
CREATE (Y)-[:Visit{time:2}]->(V)
CREATE (Y)-[:Visit{time:20}]->(im)
CREATE (M:Node{name: 'M'})
CREATE (Y)-[:Visit{time:2}]->(M)
CREATE (W:Node{name: 'W'})
CREATE (N:Node{name: 'N'})
CREATE (W)-[:Visit{time:14}]->(N)
CREATE (O:Node{name: 'O'})
CREATE (W)-[:Visit{time:77580}]->(O)
CREATE (W)-[:Visit{time:95}]->(L)
CREATE (W)-[:Visit{time:7}]->(C)
CREATE (P:Node{name: 'P'})
CREATE (W)-[:Visit{time:2}]->(P)
CREATE (Q:Node{name: 'Q'})
CREATE (W)-[:Visit{time:1}]->(Q)
CREATE (others:Node{name: 'others'})
CREATE (others)-[:Visit{time:219}]->(K)
CREATE (others)-[:Visit{time:28}]->(im)
CREATE (R:Node{name: 'R'})
CREATE (others)-[:Visit{time:222}]->(R)
CREATE (others)-[:Visit{time:59}]->(C)
CREATE (X:Node{name: 'X'})
CREATE (X)-[:Visit{time:10}]->(K)
CREATE (X)-[:Visit{time:35}]->(im)
CREATE (X)-[:Visit{time:83}]->(X)
CREATE (X)-[:Visit{time:45}]->(C)
CREATE (S:Node{name: 'S'})
CREATE (S)-[:Visit{time:8231}]->(S)
CREATE (T:Node{name: 'T'})
CREATE (S)-[:Visit{time:2851}]->(T)
CREATE (S)-[:Visit{time:4323}]->(L)
CREATE (S)-[:Visit{time:8229}]->(R)

3. 打开 Neo4j Desktop, 并启动 Graph 数据

   
   neo4j desktop - testGraph.png

4. 点击打开 "Neo4j Browser"

5. 运行命令先清理数据库

// Delete everything
MATCH (n)
DETACH DELETE n;

DETACH COMMAND.png

6. 运行上面的所有 CREATE 命令，创建节点和关系

CREATE COMMANDS.png

7. 运行命令，显示所有节点和关系
   // Display all nodes
   MATCH (n)
   RETURN n

MATCH ALL NODES.png