我有以下问题whicj我试图用级联解决:我有csv文件的记录结构:o,a,f,i,c
我需要通过o,a,f来汇总记录,并将每个组的i和c相加。
例如:
100,200,300,5,1
100,200,300,6,2
101,201,301,20,5
101,201,301,21,6
应该产生:
100,200,300,11,3
101,201,301,41,11
我无法理解如何合并我拥有的每个实例(我可以在同一时间聚合两个字段吗?)。
你有什么想法吗?
Yosi
public class CascMain {
public static void main(String[] args){
Scheme sourceScheme = new TextLine(new Fields("line"));
Tap source = new Lfs(sourceScheme, "/tmp/casc/group.csv");
Scheme sinkScheme = new TextDelimited(new Fields("o", "a", "f", "ti", "tc"), ",");
Tap sink = new Lfs(sinkScheme, "/tmp/casc/output/", SinkMode.REPLACE);
Pipe assembly = new Pipe("agg-pipe");
Function function = new RegexSplitter(new Fields("o", "a", "f", "i", "c"), ",");
assembly = new Each(assembly, new Fields("line"), function);
Pipe groupAssembly = new GroupBy("group", assembly, new Fields("o", "a", "f"));
Sum impSum = new Sum(new Fields("ti"));
Pipe i = new Every(groupAssembly, new Fields("i"), impSum);
Sum clickSum = new Sum(new Fields("tc"));
Pipe c = new Every(groupAssembly, new Fields("c"), clickSum);
// WHAT SHOULD I DO HERE
Properties properties = new Properties();
FlowConnector.setApplicationJarClass(properties, CascMain.class);
FlowConnector flowConnector = new FlowConnector(properties);
Flow flow = flowConnector.connect("agg", source, sink, assembly);
flow.complete();
}
}
答案 0 :(得分:7)
使用AggregateBy同时聚合多个字段:
SumBy impSum = new SumBy(new Fields("i"), new Fields("ti"), long.class);
SumBy clickSum = new SumBy(new Fields("c"), new Fields("tc"), long.class);
assembly = new AggregateBy("totals", Pipe.pipes(assembly), new Fields("o", "a", "f"), 2, impSum, clickSum);