Neo4j图数据库查询
- 连接neo4j数据库之后，在浏览器中使用http://localhost:7474/browser/网址查看数据库，初始账户跟密码都是neo4j
-
首先查看图数据库
双击某一个实体可以看到该实体与其他实体之间的关系
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查询疾病实体
根据疾病查询症状和药品，实体之间的关系可以从代码中看到
MATCH (d:Disease)-[:HAS_SYMPTOM]->(s) WHERE d.name='糖尿病' RETURN d.name,s.name
MATCH (d:Disease)-[:HAS_DRUG]->(drug) WHERE d.name='糖尿病' RETURN d.name,drug.name
基于知识图谱的问题系统主体类AnswerSearching介绍
class AnswerSearching:
def __init__(self):
pass
# 主要是根据不同的实体和意图构造cypher查询语句
def question_parser(self, data):
"""
主要是根据不同的实体和意图构造cypher查询语句
:param data: {"Disease":[], "Alias":[], "Symptom":[], "Complication":[]}
:return:
"""
pass
# 将问题转变为cypher查询语句
def transfor_to_sql(self, label, entities, intent):
"""
将问题转变为cypher查询语句
:param label:实体标签
:param entities:实体列表
:param intent:查询意图
:return:cypher查询语句
"""
pass
# 执行cypher查询，返回结果
def searching(self, sqls):
"""
执行cypher查询，返回结果
:param sqls:
:return:str
"""
pass
# 根据不同意图，返回不同模板的答案
def answer_template(self, intent, answers):
"""
根据不同意图，返回不同模板的答案
:param intent: 查询意图
:param answers: 知识图谱查询结果
:return: str
"""
pass
代码分模块介绍
- 在Python中我们使用py2neo进行查询
- 首先安装py2neo,pip install py2neo
- 连接上neo4j数据库
from py2neo import Graph
graph = Graph("http://localhost:7474", username="neo4j", password="neo4j")
- 根据不同的实体和意图构造cypher查询语句
def question_parser(data):
"""
主要是根据不同的实体和意图构造cypher查询语句
:param data: {"Disease":[], "Alias":[], "Symptom":[], "Complication":[]}
:return:
"""
sqls = []
if data:
for intent in data["intentions"]:
sql_ = {}
sql_["intention"] = intent
sql = []
if data.get("Disease"):
sql = transfor_to_sql("Disease", data["Disease"], intent)
elif data.get("Alias"):
sql = transfor_to_sql("Alias", data["Alias"], intent)
elif data.get("Symptom"):
sql = transfor_to_sql("Symptom", data["Symptom"], intent)
elif data.get("Complication"):
sql = transfor_to_sql("Complication", data["Complication"], intent)
if sql:
sql_['sql'] = sql
sqls.append(sql_)
return sql
- 将问题转变为cypher查询语句
def transfor_to_sql(label, entities, intent):
"""
将问题转变为cypher查询语句
:param label:实体标签
:param entities:实体列表
:param intent:查询意图
:return:cypher查询语句
"""
if not entities:
return []
sql = []
# 查询症状
if intent == "query_symptom" and label == "Disease":
sql = ["MATCH (d:Disease)-[:HAS_SYMPTOM]->(s) WHERE d.name='{0}' RETURN d.name,s.name".format(e)
for e in entities]
# 查询治疗方法
if intent == "query_cureway" and label == "Disease":
sql = ["MATCH (d:Disease)-[:HAS_DRUG]->(n) WHERE d.name='{0}' return d.name,d.treatment," \
"n.name".format(e) for e in entities]
# 查询治疗周期
if intent == "query_period" and label == "Disease":
sql = ["MATCH (d:Disease) WHERE d.name='{0}' return d.name,d.period".format(e) for e in entities
...
- 执行cypher查询，返回结果
def searching(sqls):
"""
执行cypher查询，返回结果
:param sqls:
:return:str
"""
final_answers = []
for sql_ in sqls:
intent = sql_['intention']
queries = sql_['sql']
answers = []
for query in queries:
ress = graph.run(query).data()
answers += ress
final_answer = answer_template(intent, answers)
if final_answer:
final_answers.append(final_answer)
return final_answers
- 根据不同意图，返回不同模板的答案
def answer_template(intent, answers):
"""
根据不同意图，返回不同模板的答案
:param intent: 查询意图
:param answers: 知识图谱查询结果
:return: str
"""
final_answer = ""
if not answers:
return ""
# 查询症状
if intent == "query_symptom":
disease_dic = {}
for data in answers:
d = data['d.name']
s = data['s.name']
if d not in disease_dic:
disease_dic[d] = [s]
else:
disease_dic[d].append(s)
i = 0
for k, v in disease_dic.items():
if i >= 10:
break
final_answer += "疾病 {0} 的症状有：{1}\n".format(k, ','.join(list(set(v))))
i += 1
...
