请求帮助通过 R-neo4j 进行 Cypher 查询

Question

我刚开始使用 R、neo4j 和 R-neo4j 编程，所以如果我的问题很简单，请谅解。

我使用 R-neo4j 和以下 R 项目代码 [2] 创建了以下数据库（请附上照片）[1]。

该数据库包含四名玩家之间的电脑游戏比赛结果。数据集由四个节点组成，玩家 1 到玩家 4。节点通过关系 "defeats" 连接，表示比赛的结果。每个关系都有两个标签条目，包含以下数据：judge、game。

从使用Cypher查询的图数据库中，我想提取如下形式的数据（请提供[1]中的图片）：

Winning player    Loosing player    Game         Judge
player 1          player 4          Starcraft    player 2
player 1          player 4          LOL          player 3
player 4          player 1          LOL          player 2
player 1          player 4          Starcraft    player 3
player 1          player 2          LOL          player 3
player 2          player 1          LOL          player 4
player 4          player 1          Starcraft    player 4

我想查询（R-neo4j环境下首选）图数据库，输入"player 1"返回上面的table

我希望我的问题很清楚并且有人可以帮助我。

祝你有美好的一天。

基督教徒

[1] https://goo.gl/cMxXHo

[2] R (Rneo4j) 代码：

clear(graph)
Y
player1 = createNode(graph,"user",ID="Player 1",male=T)
player2 = createNode(graph,"user",ID="Player 2",male=T)
player3 = createNode(graph,"user",ID="Player 3",male=F)
player4 = createNode(graph,"user",ID="Player 4",male=F)

addConstraint(graph,"user","ID")

rel1 = createRel(player1,"defeats",player4)
rel2 = createRel(player1,"defeats",player4)
rel3 = createRel(player4,"defeats",player1)
rel4 = createRel(player1,"defeats",player4)
rel5 = createRel(player1,"defeats",player2)
rel6 = createRel(player2,"defeats",player1)
rel7 = createRel(player3,"defeats",player1)

rel1 = updateProp(rel1, game = "Starcraft", judge = "Player 2")
rel2 = updateProp(rel2, game = "League of Legends", judge = "Player 3")
rel3 = updateProp(rel3, game = "League of Legends", judge = "Player 2")
rel4 = updateProp(rel4, game = "Starcraft", judge = "Player 3")
rel5 = updateProp(rel5, game = "League of Legends", judge = "Player 3")
rel6 = updateProp(rel6, game = "League of Legends", judge = "Player 4")
rel7 = updateProp(rel7, game = "Starcraft", judge = "Player 4")

Answer 1

几件事。如果您想使用 clear(graph) 而不必输入 "Y"，您可以使用 clear(graph, input=F)。此外，如果您不知道，您可以在创建关系时设置关系的属性：

rel1 = createRel(player1, "defeats", player4, game="Starcraft", judge="Player 2")

为了回答这个问题，我会这样做：

getDataForPlayer = function(name) {
  query = "
  MATCH (winner:user)-[game:defeats]->(loser:user)
  WHERE winner.ID = {name} OR loser.ID = {name}
  RETURN winner.ID AS `Winning Player`,
         loser.ID AS `Losing Player`,
         game.game AS Game,
         game.judge AS Judge
  "

  return(cypher(graph, query, name=name))
}

getDataForPlayer("Player 1")

输出：

  Winning Player Losing Player              Game    Judge
1       Player 4      Player 1 League of Legends Player 2
2       Player 2      Player 1 League of Legends Player 4
3       Player 3      Player 1         Starcraft Player 4
4       Player 1      Player 2 League of Legends Player 3
5       Player 1      Player 4         Starcraft Player 2
6       Player 1      Player 4 League of Legends Player 3
7       Player 1      Player 4         Starcraft Player 3

Answer 2

看着你的图表，我觉得结构不正确。尽管每个场景可能不同，但考虑添加更多数据时会发生什么总是好的。你的模型可以处理吗？

比如你用关系来表示比赛的结果，那当然需要属性来存储裁判和比赛。游戏名称对我来说实际上看起来像锦标赛游戏，但你会知道哪个更好用。在存储球员和锦标赛名称时，您最终会出现很多重复，因为相同的名称和球员随处可见。

如果您继续在玩家之间添加结果，您最终会得到很多关系，并且错误和重复的可能性会不断增加。

那你可以做些什么来改进你的模型呢？将您的基本关系视为起点，但现在它已经超出了最初的要求：您可以为锦标赛引入节点，为游戏引入节点；保持关系以存储玩家在游戏中的角色等。总是有不止一种方法可以做到这一点 (TIMTOWTDI)。

一图抵千字，看这里的改进模型：

您会看到如何更轻松地向模型中的相应节点或关系添加其他属性。

为了产生您想要的 table 结果，您可以使用：

MATCH
  (g:Game)-[:WINNER]->(w:Player),
  (g)-[:LOSER]->(l:Player),
  (g)-[:JUDGE]->(j:Player),
  (g)<-[:HAS_GAMES]-(t:Tournament)
WHERE
  w.name = 'Player 1' OR l.name = 'Player 1'
RETURN
  w.name AS 'Winning Player',
  l.name AS 'Losing Player',
  t.name AS 'Game',
  j.name AS 'Judge'

并按照 Nicole 的建议适应 R。如果你假装添加很多数据，我认为这种结构会更好地适应你的需求，你也可以探索查询相同数据的不同方式，因为你现在可以从锦标赛开始或直接探索游戏。

请求帮助通过 R-neo4j 进行 Cypher 查询

Request for help wirting Cypher query through R-neo4j

r

neo4j

cypher

r-neo4j