Hey Mike,

My only concern is that I am replacing a large number of fields inside of a 
Document with a (very large ~50e6) number of Documents.  Will I not run into 
the same memory issues?  Or do I create only one doc object and reuse it?  With 
so many Doc/Token pairs, won't searching the index take a lot more time?

Thanks for your help,
Chris

On May 5, 2011, at 3:11 PM, Mike Sokolov wrote:

> I think the solution I gave you will work.  The only problem is if a token 
> appears twice in the same doc:
> 
> doc1 has foo with two different sets of weights and frequencies...
> 
> but I think you're saying that doesn't happen
> 
> On 05/05/2011 06:09 PM, Chris Schilling wrote:
>> Hey Mike,
>> 
>> Let me clarify:
>> 
>> The tokens are not unique.  Let's say doc1 contains the token
>> foo and has the properties weight1 = 0.75, weight2 = 0.90, frequency = 10
>> 
>> Now, let's say doc2 also contains the token
>> foo with properties: weight1 = 0.8, weight2 = 0.75, frequency = 5
>> 
>> Now, I want to search for all the documents that contain foo, but I want 
>> them sorted by frequency.
>> 
>> Then, I would have doc1, doc2.
>> 
>> Now, I want to search for all the documents that contain foon, but I want 
>> them sorted by weight1.
>> Then, I would have doc2, doc1
>> 
>> Does that clarify?
>> 
>> 
>> On May 5, 2011, at 3:01 PM, Mike Sokolov wrote:
>> 
>>   
>>> Are the tokens unique within a document? If so, why not store a document 
>>> for every doc/token pair with fields:
>>> 
>>> id (doc#/token#)
>>> doc-id (doc#)
>>> token
>>> weight1
>>> weight2
>>> frequency
>>> 
>>> Then search for token, sort by weight1, weight2 or frequency.
>>> 
>>> If the token matches are unique within a document you will only get each 
>>> document listed once.  If they aren't unique, it's not clear what you want 
>>> to sort by anyway....
>>> 
>>> -Mike
>>> 
>>> On 05/05/2011 04:12 PM, Chris Schilling wrote:
>>>     
>>>> Hi,
>>>> 
>>>> I am trying to figure out how to solve this problem:
>>>> 
>>>> I have about 500,000 files that I would like to index, but the files are 
>>>> structured.  So, each file has the following layout:
>>>> 
>>>> doc1
>>>> token1, weight11, frequency1, weight21
>>>> token2, weight12, frequency2, weight22
>>>> .
>>>> .
>>>> .
>>>> 
>>>> etc for 500,000 docs.
>>>> 
>>>> Basically, I would like to index the tokens for each doc.  When I search 
>>>> for a token, I would like to be able to return the top docs sorted by 
>>>> weight1, frequency, or weight2.
>>>> 
>>>> So, in my naive setup, I loop through the files in the directory, then I 
>>>> loop through the lines of the file.   In side of the loop through each 
>>>> file, I call this function:
>>>> 
>>>>    public Document processKeywords(Document doc, String keyword, Float 
>>>> weight1, Float weight2, Integer frequency) throws Exception {
>>>>                    Document doc = new Document();
>>>>                    doc.add(new Field("keywords", keyword, Field.Store.NO, 
>>>> Field.Index.ANALYZED));                  
>>>>                    doc.add(new NumericField(keyword+"weight1", 
>>>> Field.Store.YES, true).setFloatValue(weight1));                     
>>>>                    doc.add(new NumericField(keyword+"weight2", 
>>>> Field.Store.YES, true).setFloatValue(weight2));                     
>>>>                    doc.add(new NumericField(keyword+"frequency", 
>>>> Field.Store.YES, true).setFloatValue(frequency));                 
>>>>                    return doc;
>>>>    }
>>>> 
>>>> So, for each token, I create 3 new fields each time. Notice how I am 
>>>> trying to index the keyword in the "keywords" field.  For the weights and 
>>>> frequency, I create a new field with a name based on the keyword.  On 
>>>> average, I have 100 tokens per document, so each document will have about 
>>>> 300 distinct fields.
>>>> 
>>>> When running my program, the lucene portion eats up tons of memory and 
>>>> when it gets to the max alloted by the JVM (I have tried allowing up to 4 
>>>> Gb), the program slows to a crawl.  I assume it is spending all of its 
>>>> time in garbage collection due to all these fields.
>>>> 
>>>> My code above seems like a very hacky way of accomplishing what I want 
>>>> (sorting documents based on keyword search using different numeric fields 
>>>> associated with that keyword).
>>>> 
>>>> FYI, here is the main search code, where q is the token I am searching for 
>>>> and sortby is the field I want to use to sort.  I setup a QP to search for 
>>>> the keyword in the "keywords" field.  Then, I can extract the stats that I 
>>>> indexed for the given query keyword.
>>>> 
>>>>    private static final QueryParser parser = new 
>>>> QueryParser(Version.LUCENE_30, "keywords", new 
>>>> StandardAnalyzer(Version.LUCENE_30));
>>>> 
>>>>    public void search(String q, String sortby) throws IOException, 
>>>> ParseException {
>>>>            Query query = parser.parse(q);
>>>>            long start = System.currentTimeMillis();
>>>>            TopDocs hits = this.is.search(query, null, 10, new Sort(new 
>>>> SortField(q+"sortby", SortField.FLOAT, true)));
>>>>            long end = System.currentTimeMillis();
>>>>            System.out.println("Found " + hits.totalHits +
>>>>                            " document(s) (in " + (end - start) +
>>>>                            " milliseconds) that matched query '" +
>>>>                            q + "':");
>>>>            for(ScoreDoc scoreDoc : hits.scoreDocs) {
>>>>                    Document doc = this.is.doc(scoreDoc.doc);
>>>>                    String hash = doc.get("hash");
>>>>                    System.out.println(hash + " " + doc.get(q+"sortby") + " 
>>>> " + hash);
>>>>            }
>>>>    }
>>>> 
>>>> I am pretty new to Lucene, so I hope this makes sense.  I tried to pare my 
>>>> problem down as much as possible.  Like I said, the main problem I am 
>>>> running into is that after processing about 30000 documents, the indexing 
>>>> slows to a crawl and seems to spend all of its time in the garbage 
>>>> collector.  I am looking for a more efficient/effective way of solving 
>>>> this problem.  Code tidbits would help, but are not necessary :)
>>>> 
>>>> Thanks for your help,
>>>> Chris S.
>>>> 
>>>>       
>>   


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