Cypher查詢匹配所有路徑

Question

我有一個像「項目」，「員工」和「技術」節點的圖形。項目與技術之間以及員工與技術之間存在關係。

我想找到知道項目使用的所有技術的員工。我cyper查詢看起來是這樣的：

start project=node:project(name = "Project1") 
match technology <-[:USED]- project , employee -[:KNOWS]-> technology 
return employee 

當運行此查詢我得到了解工程使用的一種技術，並且希望那些知道該項目使用的所有技術員工的所有員工。這是可能的密碼？

Answer 1

你可以嘗試這樣的：

start project=node:project(name = "Project1") 
match employee -[:KNOWS]-> technology <-[:USED]- project 
with count(technology) as knownTech, employee, project 
where length(()<-[:USED]-project)=knownTech 
return employee 

見Finding nodes that have all common intermediaries

Answer 2

我可能會利用這一點避免計算每名員工由項目使用的技術數量：

start project=node:project(name = "Project1") 
match technology <-[:USED]- project 
with count(technology) as projectTech, project 
match employee -[:KNOWS]-> technology <-[:USED]- project 
with count(technology) as knownTech, projectTech, employee 
where projectTech=knownTech 
return employee