在ArangoDB中实现connectedcomponents算法

操作环境：

tool：ArangoDB 3.3.13

操作系统：Debian 7.2.0-20

概念：

Connected Components即连通体算法。用id标注图中每个连通体，将连通体中序号最小的顶点的id作为连通体的id。

如果在图G中，任意2个顶点之间都存在路径，那么称G为连通图，否则称该图为非连通图，则其中的极大连通子图称为连通体，如下图所示，该图中有两个连通体：

实例：

创建集合

//testv
LET data = [{"_key":"6014c5cac3424d8386dac12c46017c03","host_name":"Salih Tektase"},
{"_key":"6014c5ccca5b4cae893257bf86f0ead0","host_name":"Aditya Bramhan"},
{"_key":"6014c5c80177417fbfd0faf9d5fb31a4","host_name":"Ica palya"},
{"_key":"6014c5c891e54e4a8903cd306d55eb26","host_name":"null"},
{"_key":"6014c5c8f29d426686d6c30152a01459","host_name":"Boanny Patel"},
{"_key":"6014c5ccd2484a4581137ab8aa245ba7","host_name":"El Chapo"},
{"_key":"6014c5c8f1cb47ff886dd1991d19e59d","host_name":"Andrej Altuchov"},
{"_key":"6014c5dd17b54eda83e02e8dd913dba0","host_name":"Maria"},
{"_key":"6014c5e78bfd4051a421bd6adf017e56","host_name":"null"},
{"_key":"6014c5f1c88e40a6a1aa88da08d7c404","host_name":"Aaron Villaflor"}]

for d in data
    insert d into testv

//teste
LET data = [{"_key":"","_from":"testv/6014c5ccca5b4cae893257bf86f0ead0","_to":"testv/6014c5cac3424d8386dac12c46017c03"},
{"_key":"","_from":"testv/6014c5c80177417fbfd0faf9d5fb31a4","_to":"testv/6014c5cac3424d8386dac12c46017c03"},
{"_key":"","_from":"testv/6014c5ccd2484a4581137ab8aa245ba7","_to":"testv/6014c5c8f29d426686d6c30152a01459"},
{"_key":"","_from":"testv/6014c5e78bfd4051a421bd6adf017e56","_to":"testv/6014c5dd17b54eda83e02e8dd913dba0"},
{"_key":"","_from":"testv/6014c5f1c88e40a6a1aa88da08d7c404","_to":"testv/6014c5dd17b54eda83e02e8dd913dba0"},
{"_key":"","_from":"testv/6014c5c8f29d426686d6c30152a01459","_to":"testv/6014c5c891e54e4a8903cd306d55eb26"},
{"_key":"","_from":"testv/6014c5c891e54e4a8903cd306d55eb26","_to":"testv/6014c5ccd2484a4581137ab8aa245ba7"},
{"_key":"","_from":"testv/6014c5c8f1cb47ff886dd1991d19e59d","_to":"testv/6014c5e78bfd4051a421bd6adf017e56"}]

for d in data
    insert d into teste

//teste2
LET data = [{"_key":"","_from":"testv/6014c5cac3424d8386dac12c46017c03","_to":"testv/6014c5ccca5b4cae893257bf86f0ead0"},
{"_key":"","_from":"testv/6014c5cac3424d8386dac12c46017c03","_to":"testv/6014c5c80177417fbfd0faf9d5fb31a4"},
{"_key":"","_from":"testv/6014c5dd17b54eda83e02e8dd913dba0","_to":"testv/6014c5e78bfd4051a421bd6adf017e56"},
{"_key":"","_from":"testv/6014c5c891e54e4a8903cd306d55eb26","_to":"testv/6014c5c8f29d426686d6c30152a01459"},
{"_key":"","_from":"testv/6014c5c8f29d426686d6c30152a01459","_to":"testv/6014c5ccd2484a4581137ab8aa245ba7"},
{"_key":"","_from":"testv/6014c5dd17b54eda83e02e8dd913dba0","_to":"testv/6014c5f1c88e40a6a1aa88da08d7c404"},
{"_key":"","_from":"testv/6014c5ccd2484a4581137ab8aa245ba7","_to":"testv/6014c5c891e54e4a8903cd306d55eb26"},
{"_key":"","_from":"testv/6014c5e78bfd4051a421bd6adf017e56","_to":"testv/6014c5c8f1cb47ff886dd1991d19e59d"}]

for d in data
    insert d into teste2

创建图

运行算法

var pregel = require("@arangodb/pregel")
var handle = pregel.start("connectedcomponents", "cc", {maxGSS: , resultField: "component"})

查看进程：

var status = pregel.status(handle);

结果

参考资料：

https://github.com/arangodb/arangodb/issues/4062

https://blog.csdn.net/zryowen123/article/details/77386992