我试图使用PIG从xml文件中读取数据,但我的输出不完整.
输入文件-
- <document>
- <url>htp://www.abc.com/</url>
- <category>Sports</category>
- <usercount>120</usercount>
- <reviews>
- <review>good site</review>
- <review>This is Avg site</review>
- <review>Bad site</review>
- </reviews>
- </document>
我正在使用的代码是：
- register 'Desktop/piggybank-0.11.0.jar';
- A = load 'input3' using org.apache.pig.piggybank.storage.XMLLoader('document') as (data:chararray);
- B = foreach A GENERATE FLATTEN(REGEX_EXTRACT_ALL(data,'(?s)<document>.*?<url>([^>]*?)</url>.*?<category>([^>]*?)</category>.*?<usercount>([^>]*?)</usercount>.*?<reviews>.*?<review>\\s*([^>]*?)\\s*</review>.*?</reviews>.*?</document>')) as (url:chararray,catergory:chararray,usercount:int,review:chararray);
我得到的输出是：
- (htp://www.abc.com/,Sports,120,good site)
这是不完整的输出.有人请帮助我失踪了吗？
呵呵！终于让它使用cross工作了.我正在使用XPath,如果你愿意,你可以使用正则表达式.我发现,XPath比正则表达式更简单,更清晰.我想,你也可以看到它.不要忘记用XML替换testXML.xml.
XPath方式：
- DEFINE XPath org.apache.pig.piggybank.evaluation.xml.XPath();
- A = LOAD 'testXML.xml' using org.apache.pig.piggybank.storage.XMLLoader('document') as (x:chararray);
- B = FOREACH A GENERATE XPath(x,'document/url'),XPath(x,'document/category'),'document/usercount');
- C = LOAD 'testXML.xml' using org.apache.pig.piggybank.storage.XMLLoader('review') as (review:chararray);
- D = FOREACH C GENERATE XPath(review,'review');
- E = cross B,D;
- dump E;
正则表达方式：
- A = LOAD 'testXML.xml' using org.apache.pig.piggybank.storage.XMLLoader('document') as (x:chararray);
- B = FOREACH A GENERATE FLATTEN(REGEX_EXTRACT_ALL(x,'(?s)<document>.*?<url>([^>]*?)</url>.*?<category>([^>]*?)</category>.*?<usercount>([^>]*?)</usercount>.*?</document>')) as (url:chararray,usercount:int);
- C = LOAD 'testXML.xml' using org.apache.pig.piggybank.storage.XMLLoader('review') as (review:chararray);
- D = FOREACH C GENERATE FLATTEN(REGEX_EXTRACT_ALL(review,'<review>([^>]*?)</review>'));
- E = cross B,D;
- dump E;
输出：
- (htp://www.abc.com/,Bad site)
- (htp://www.abc.com/,This is Avg site)
- (htp://www.abc.com/,good site)
这不是你所期待的吗？
