- 查詢John的朋友的朋友
添加5個人名節點，名字分別爲
CREATE (:People{name:"John"})
CREATE (:People{name:"Joe"})
CREATE (:People{name:"Sara"})
CREATE (:People{name:"Steve"})
CREATE (:People{name:"Maria"})
此時查詢所有人的結果如下
match (people:People) return people
給這5個人添加上朋友關係
MATCH (a:People{name:"John"}) MATCH (b:People{name:"Joe"}) CREATE (a) -[:friend]->(b)
MATCH (a:People{name:"John"}) MATCH (b:People{name:"Sara"}) CREATE (a) -[:friend]->(b)
MATCH (a:People{name:"Joe"}) MATCH (b:People{name:"Steve"}) CREATE (a) -[:friend]->(b)
MATCH (a:People{name:"Sara"}) MATCH (b:People{name:"Maria"}) CREATE (a) -[:friend]->(b)
再次查詢
match (people:People) return people
查詢John朋友的朋友的名字
match (john {name:'John'})-[:friend]->()-[:friend]->(fof) return john.name,fof.name
結果
因爲這裏查詢的只是名字，而不是節點，所以只會顯示各自的名稱。
- 給定一個用戶名列表，找到名字在列表中的所有節點。匹配他們的朋友，僅返回那些他們關注的name屬性以'S'開頭的用戶
match (user)-[:friend]->(follower) where user.name in ['Joe','John','Sara','Maria','Steve']
and follower.name =~'S.*' return user.name,follower.name
結果
- 獲取John和他的朋友數量
match (n {name:'John'})-[:friend]->(friend) with n,count(friend) as friendsCount return n,friendsCount
- 獲取John的朋友數量並保存爲John的一個屬性
match (n {name:'John'})-[:friend]->(friend) with n,count(friend) as friendsCount set n.friendsCount=friendsCount return n.friendsCount
- 查詢朋友的朋友，不包含自己
添加3個用戶，兩個好友關係
create (adam:User {name:'Adam'}),(pernilla:User {name:'Pernilla'}),
(david:User {name:'David'}),(adam)-[:friend]->(pernilla),
(pernilla)-[:friend]->(david)
查詢結果
match (n:User) return n
match (user {name:'Adam'})-[:friend]->()-[:friend]->(friend) return friend
match (user {name:'Adam'})-[:friend]->(friend),(friend)-[:friend]-(alluser) return alluser
該方式也是不包含自己的，可以與下面包含自己的做出比較。
- 查詢朋友的朋友，包含自己
match (user {name:'Adam'})-[:friend]->(friend) match (friend)-[:friend]-(alluser) return alluser![]()
