apoc.path.slice
语法 |
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描述 |
从给定 `PATH` 的给定偏移量处,返回一个指定长度的新 `PATH`。 |
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参数 |
名称 |
类型 |
描述 |
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要切片的路径。 |
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新路径的起始偏移量。默认值为:`0`。 |
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新路径的长度。默认值为:`-1`。 |
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返回值 |
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使用示例
本节示例基于以下示例图
MERGE (manUtd:Club {name: 'Man Utd'})
MERGE (juventus:Club {name: 'Juventus'})
MERGE (flamengo:Club {name: 'Flamengo'})
MERGE (premierLeague:League {name: 'Premier League'})
MERGE (serieA:League {name: 'Serie A'})
MERGE (brasileirao:League {name: 'Brasileirão'})
MERGE (england:Country {name: 'England'})
MERGE (brazil:Country {name: 'Brazil'})
MERGE (uefa:Confederation {name: 'UEFA'})
MERGE (manUtd)-[:IN_LEAGUE]->(premierLeague)
MERGE (premierLeague)-[:IN_COUNTRY]->(england)
MERGE (england)-[:IN_CONFEDERATION]->(uefa)
MERGE (juventus)-[:IN_LEAGUE]->(serieA)
MERGE (flamengo)-[:IN_LEAGUE]->(brasileirao)
MERGE (brasileirao)-[:IN_COUNTRY]->(brazil);
apoc.path.slice 函数返回路径的一个子集,从指定偏移量开始,包含指定数量的元素。
以下返回合并路径的一个子集,从偏移量 1 开始,长度为 1
MATCH (club:Club)
OPTIONAL MATCH path1 = (club)-[:IN_LEAGUE]->(league)
OPTIONAL MATCH path2 = (league)-[:IN_COUNTRY]->(country)
WITH apoc.path.combine(path1, path2) AS path
RETURN apoc.path.slice(path, 1, 1);
| apoc.path.slice(path, 1, 1) |
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(:League {name: "Premier League"})-[:IN_COUNTRY]→(:Country {name: "England"}) |
(:League {name: "Serie A"}) |
(:League {name: "Brasileirão"})-[:IN_COUNTRY]→(:Country {name: "Brazil"}) |