猪的过滤器匹配太多 [英] Too many filter matching in pig

问题描述

我有一个过滤关键字列表(大约有 1000 个)，我需要使用这个列表过滤 pig 中关系的一个字段.

I have a list of filter keywords (about 1000 in numbers) and I need to filter a field of a relation in pig using this list.

最初，我声明了这些关键字，例如:%declare p1 '.keyword1.';.......

Initially, I have declared these keywords like: %declare p1 '.keyword1.'; .... ...

%declare p1000 '.keyword1000.';

%declare p1000 '.keyword1000.';

然后我正在做如下过滤:

I am then doing filtering like:

Filtered= FITLER SRC BY(不是 $0 匹配 '$p1')和(不是 $0 匹配 '$p2')和......(不是 $0 匹配 '$p1000')；

Filtered= FITLER SRC BY (not $0 matches '$p1') and (not $0 matches '$p2') and ...... (not $0 matches '$p1000');

转储过滤;

假设我的源关系在 SRC 中，我需要对第一个字段(即 $0)应用过滤.

Assume that my source relation is in SRC and I need to apply filtering on first field i.e. $0.

如果我将过滤器的数量减少到 100-200，它就可以正常工作.但随着过滤器数量增加到 1000.它不起作用.

If I am reducing the number of filters to 100-200, it's working fine. But as number of filters increases to 1000. It doesn't work.

有人可以建议解决方法来获得正确的结果吗?

Can somebody suggest a work around to get the results right?

提前致谢

推荐答案

您可以编写一个简单的过滤器 UDF，在其中执行所有检查，例如:

You can write a simple filter UDF where you'd perform all the checks something like:

 package myudfs;
 import java.io.IOException;
 import org.apache.pig.FilterFunc;
 import org.apache.pig.data.Tuple;

 public class MYFILTER extends FilterFunc
 {
    static List<String> filterList;
    static MYFILTER(){
        //load all filters
    }
    public Boolean exec(Tuple input) throws IOException {
        if (input == null || input.size() == 0)
            return null;
        try{
            String str = (String)input.get(0);
           return !filterList.contains(str);
        }catch(Exception e){
            throw new IOException("Caught exception processing input row ", e);
        }
    }

  }

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