CREATE (erzi:Person {id:'erzi'}),
(baba:Person {id:'baba'}),
(yeye:Person {id:'yeye',name:'zhangsan'}),
(nainai:Person {id:'nainai'}),
(mama:Person {id:'mama'}),
(bozi:Person {id:'bozi'}),
(erzi)-[:fathor]->(baba),
(baba)-[:fathor]->(yeye),
(baba)-[:mother]->(nainai),
(erzi)-[:mother]->(mama),
(erzi)-[:girlFrend]->(bozi)
自动匹配类型,不用声明类型 对比sql语法如下:
create (n:Person {id:'20140101',name:'王五',age:30,card:123456})
相当于关系Sql的:
Create table Person(
id varchar2,
name varchar2,
age number,
card number );
Insert into Person values(‘20140101’,’王五’,30,123456);
image.png
相当于select
查询某一个节点,需要给一个属性
方法一:
match(n:hero {name:"孙尚香"}) return n
方法二:
match(n:hero) where n.name="孙尚香" return n
查询关系:
match (n:Person {id:'baba'})-[:fathor]-(f) return n,f
match (n:Person {id:'baba'})-[:fathor]->(f) return n,f
match (n:Person {id:'baba'})-[:fathor]-(f) return f
Match (n:Person {id:'erzi'}),(f:Person {id:'bozi'})
Merge (n)-[:fuqi]->(f)
Match (n:Person ),(f:Person)
where n.id='erzi' and f.id='bozi'
Merge (n)-[r:fuqi]->(f) delete r
Merge (n)-[:FUQI]->(f)
return n,f
关系大小写区分的
Merge等于Match或者create
Cypher中无Update,用set代替
更新属性
Match (n:Person {id:'baba'}) set n.name='张三' return n
属性名是写数据时自动创建,无schme特性,这点同no-sql库;
支持非结构化数据; 非结构化:不同行的数据可以有不同的列个数;
Match (n:Person {id:'baba'}) set n.name='张三',n.age=50 return n
Cypher语言中,任意语法都可以有return
Remove label 等同于drop table
两个命令都应该与MATCH命令一起使用。
Match (n:Person {id:'baba'}) remove n.age return n
MATCH (s:Teacher)-[r:teach]->(d:Student) delete r,s,d //删除与该关系相关的老师和学生及label
MATCH (n:Test) remove n:Test //删除label
如何仅仅删除一个relation?
Match (a:Person),(b:Person) where a.id='erzi' and b.id='bozi' merge (a)-[r:FUQI]->(b) DELETE r