Neo4j實戰之Cypher

CREATE (n:Person { name: 'Andres', title: 'Developer' }) return n;
CREATE (n:Person { name: 'Vic', title: 'Developer' }) return n;

CREATE (n:Program { name: 'java', title: 'IT' }) return n;

CREATE (n:Program { name: 'c', title: 'IT' }) return n;

CREATE (n:Program { name: 'python', title: 'IT'  }) return n;
//建立節點
CREATE (n:Program { name: 'cpp', title: 'IT' }) return n;

CREATE (n:Person { name: 'Jly', title: 'Developer' , age : 16 }) return n;

CREATE (n:Person { name: 'Zd', title: 'Developer' , age : 18 }) return n;

//建立關係    create  unique
match(n:Person{name:"Vic"}),(m:Program{name:"c"}) create (n)-[r:hasAbility]->(m) return r;

match(n:Person{name:"Vic"}),(m:Program{name:"java"}) create (n)-[r:hasAbility]->(m) return r;

match(n:Person{name:"Vic"}),(m:Program{name:"cpp"}) create (n)-[r:hasAbility]->(m) return r;

match(n:Person{name:"Andres"}),(m:Program{name:"python"}) create (n)-[r:hasAbility]->(m) return r;

match(n:Person{name:"Vic"}),(m:Person{name:"Andres"}) create (n)-[r:Friend]->(m) return r;

match(n:Person{name:"Vic"}),(m:Person{name:"Andres"}) create (n)<-[r:Friend]-(m) return r;

match(n:Person{name:"Jly"}),(m:Person{name:"Zd"}) create (n)<-[r:Friend]-(m) return r;

match(n:Person{name:"Andres"}),(m:Person{name:"Zd"}) create (n)<-[r:Friend]-(m) return r;

//刪除
match(a:Person{name:"Andres"})-[r:Friend]-(a) delete r ;

//更新
match(a:Person{name:"Andres"}) set a.hair='red' ;

match(:Person{name:"Andres"})-[:Friend]->(b) return b ;

//匿名關係  
match(:Person{name:"Andres"})-[:Friend]->(b),(b)-[:hasAbility]->(c) return c ;

//匿名節點()
match(n:Person{name:"Vic"}),(n)-[r:Friend]->() return r;

match (n:Person { name: 'Andres'})
return n;

//條件用
match(n:Person{name:"Vic"}),(m:Person{name:"Andres"}),(n)-[r:Friend]->(m) return r;

// 逗號 隔開 表明AND   以下  定義了兩個c
match(:Person{name:"Andres"})-[:Friend]->(b),(b)-[:hasAbility]->(c),(c:Program{name:"cpp"}) return c ;

//where 語句
match (a:Person{name:"Andres"})-[:Friend]->(b),(b)-[:hasAbility]->(c) where not (a)-[:hasAbility]->(c)   return c ;

match(:Person{name:"Andres"})-[:Friend]->(b),(b)-[:hasAbility]->(c),(c:Program{name:"cpp"}) return c ;

match (n:Person { title: 'Developer'})
return n;

//匹配全部節點
match(n)
return n;

//根據編號查詢   測試這裏的start不能省略    
start n=node(0,20)
return n;

//distinct 去重 ，貌似沒看到重複
start n=node(0,20)
match (n)-[:hasAbility]->(c)
return  c;

//建立索引
CREATE INDEX ON :Person(name);

CREATE INDEX ON :Program(name);

//索引查找
MATCH (p:Person {name: 'Andres'}) 
RETURN p;

match (p:Person)
where p.title='Developer'
return p;

//能夠返回倆值
match (p:Person),(n:Person)
where p.name='Zd'
return p,n;

//order by  limit  skip
match (p:Person)
where p.title='Developer'
return p
order by p.name desc
skip 1
limit 2

//支持正則表達式匹配  =~/.*@qq.com/

//has()函數   Unknown function 'has' 實測：不可用
match (p:Person)
where has(p.age)
return p;

//複雜查詢性能 Cypher不如 java api 

//查詢 Friend關係全部節點   支持count函數，sum avg max min 
start n=node(*)
match (n)-[:Friend]-()
return n,count(*)

//關係標識符TYPE 結果以關係類型分組
start n=node(*)
match (n)-[rel]-()
return TYPE(rel),count(*)

//Andres與Jly 爲好友關係（1至3層擴線）的節點    返回的是整個路徑
MATCH (p:Person {name: 'Vic'}),(n:Person {name: 'Jly'}),k=(p)-[:Friend*1..3]-(n)
RETURN k;

//ALL 每個單個元素都匹配  實測不支持   
//cypher 1.8  使用的版本
cypher 1.8 match (p:Person)
where ALL(
        user in NODES(p) 
        where user.title='Developer'
    )
return p

//管道語句 with    保存中間數據結果 start n=node(*) match (n)-[rel]-() with TYPE(rel) as type,count(*) as count where count>8 return type,count