After having performed a search in Lucene/Solr without having specified a field, how can I know in which fields of a result document the search string was found (and how often)?
You could use Query Highlighting.
Try setting debugQuery=on. See this example.
As mentioned, use debugQuery=true. The response will then include an "explain" section. By default, this will give you some awful formatted text that looks like this:
0.69102794 = (MATCH) weight(body:arrai^1.5 in 6357), product of:
0.46610788 = queryWeight(body:arrai^1.5), product of:
1.5 = boost
5.591044 = idf(docFreq=55709, maxDocs=5492855)
0.055577915 = queryNorm
1.4825494 = (MATCH) fieldWeight(body:arrai in 6357), product of:
2.828427 = tf(termFreq(body:arrai)=8)
5.591044 = idf(docFreq=55709, maxDocs=5492855)
0.09375 = fieldNorm(field=body, doc=6357)
For each match in each field, you will get a block like this that explains how SOLR computed the relevancy of this document to your query. What you're asking about (how many matches in this document's field) SOLR calls term frequency "tf". You can see this on the 7th line of the output i pasted above. In this line, SOLR is telling you that it found 8 matches for arrai in the field called "body".
The other lines stand for things like inverse document frequency-"idf" (how rare the matched term is) and fieldNorm, which relates to how short the document's field is relative to the match. You can learn about these here: http://wiki.apache.org/solr/SolrRelevancyFAQ
FYI if you need this "explain" information in a structured format instead of clumsy text you can pass this parameter with your query: debug.explain.structured=true However, its still pretty hard to use = )
Related
The following queries column A in a published Google Spreadsheet. The result is all rows with text comment in them.
var word = "comment";
var id = "unBCxSc8hR41dg6s6N3d17uccj8jnK5Xsn68C58Y76r9";
var url = "https://docs.google.com/spreadsheets/d/"+id+"/gviz/tq?tq=SELECT%20*%20where%20A%20contains%20%22"+word+"%22";
Please tell me what changes should I make to the URL in order to use regex.
For example, I need to find all rows with pattern co..en.* or .*ment in them.
~·~·~·~·~·~·~·~·~·~·~·~·~·~·~·~·~·~·~·~
EDIT
After Tanaike's help:
var word = "f.*t";
var columna = "A";
var id = "4tz810VLT4qv7Q9t94p24tz810VLT4qv7Q9t94p24tz8";
var url = "https://docs.google.com/spreadsheets/d/"+id+"/gviz/tq?tq=select%20"+columna+"%20where%20A%20matches%20%27"+word+"%27";
This will match fit, faint, font, fruit, feet, fat, etc.
~ finis ~
You want to retrieve the values using the regex of co..en.* or .*ment.
You want to achieve this using the query language of Google Visualization API.
If my understanding is correct, how about this answer? Please think of this as just on of several possible answers.
In this case, how about using matches? The modified query is as follows.
Modified query:
select * where A matches 'co..en.*|.*ment'
In this case, in order to use this query, please encode it with the URL encode. So when your endpoint is modified, please modify as follows.
From:
tq=SELECT%20*%20where%20A%20contains%20%22"+word+"%22"
To:
tq=select%20%2A%20where%20A%20matches%20%27co..en.%2A%7C.%2Ament%27
Reference:
Query Language Reference
If I misunderstood your question and this was not the result you want, I apologize.
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Geograpy (8)
Study Db (18)
i am implement my own advance search in alfresco. i need to read all files which related with particular category.
example:
if there is 20 file under geograpy, lucene query should read particular document under search key word "banana".
Further explanation -
I am using search.lib.js to search. I would like to analyze the result to find out to which category the documents belong to. For example I would like to know how many documents belong to the category under Languages and the subcategories. I experimented with the Classification API but I don't get the result I want. Any Idea how to go through the result to get the category name of each document?
is there any simple method like node.properties["cm:creator"]?
thanks
janaka
I think you should specify more your question:
Are you using cm:content or a customized content?
Are you going to search the keyword inside the content of the file? or are you going to search the keyword in a specific metadata(s)?
Do you want to create a webscript (java or javascript)?
One thing to take in consideration:
if you use +PATH:"cm:generalclassifiable/...." for the categorization in your lucene queries, the performance will be slow (following my experince)
You can use for example the next query to find all nodes at any depth below /cm:Languages:
var results = search.luceneSearch("+PATH:\"cm:generalclassifiable/cm:Languages//*\");
Take a look to this url: https://wiki.alfresco.com/wiki/Search#Path_Queries
Once you have all the elements, you can loop all, and get to which category below. Of course you need to create some counter per each category/subcategory:
for(i = 0; i < results.length; i++){
var node = results[i];
var categoryNodeRef = node.properties["cm:categories"];
var categoryDesc = categoryNodeRef.properties["cm:description"];
var categoryName = categoryNodeRef.properties["cm:name"];
}
This is not exactly the solution, but can be a useful idea to start.
Sorry if it's not what you're asking for, I have just arrived from my holidays.
I need to write lucene query/filter to get objects without specific property.
I tried with ... ISNULL:"cm:param_name" but id didn't work.
Edit: I have added new property in aspect but objects that haven't been updated yet don't have it amongst their listed properties (checked with node browser).
With a query like "cm:*", you should only receive documents that have the field "cm" plus content. Note that you have to allow leading wildcard queries by the query parser with setAllowLeadingWildcard(true).
Also check out this post, which deals with a reversed version of your problem:
Find all Lucene documents having a certain field
Can you please be more clear as to what "without property" means ? Do you mean that you do not want to specify the field like so "field:value" and instead set the filter to "value" ?
EDIT
Are you generating these field names dynamically or is this the only field name that can have it's value missing ? If there is only one field that may or may not appear in your document then you could just populate it with a default value when it's missing and then search for that . Otherwise, you could try a negated rangequery like so : NOT foo:[* TO *] . This should match all documents without a value in the foo field. For performance purposes , in the second case the field should be indexed as a string field (not analyzed).
I managed to get this done with .. AND NOT (#namespace\:property:"")
In Java and Lucene 3.6.2 the "FieldValueFilter" with activated negation can be used: (which was not the question)
import org.apache.lucene.search.FieldValueFilter;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.TopDocs;
final IndexSearcher indexSearcher = getIndexSearcher() <- whereever that comes from
final TopDocs topdocs = indexSearcher.search(new MatchAllDocsQuery(), new FieldValueFilter("cm", true), Integer.MAX_VALUE);
You can use ISUNSET and/or ISNULL for this scenario.
ISUNSET:"cm:title"
ISNULL:"cm:title"
I would like to use Lucene to index/search text. The text can contain mistyped words, names, etc. What is the most simple way of getting Lucene to find a document containing
"this is Licene"
when user searches for
"Lucene"?
This is only for a demo app, so we need the most simple solution.
Lucene's fuzzy queries and based on Levenshtein edit distance.
Use a fuzzy query in the QueryParser, with syntax like:
Lucene~0.5
Or create a FuzzyQuery, passing in the maximum number of edits, something like:
Query query = new FuzzyQuery(new Term("field", "lucene"), 1);
Note: FuzzyQuery, in Lucene 4.x, does not support greater edit distances than 2.
Another option you could try is using the Lucene SpellChecker:
http://lucene.apache.org/core/6_4_0/suggest/org/apache/lucene/search/spell/SpellChecker.html
It is a out of box, and very easy to use:
SpellChecker spellchecker = new SpellChecker(spellIndexDirectory);
// To index a field of a user index:
spellchecker.indexDictionary(new LuceneDictionary(my_lucene_reader, a_field));
// To index a file containing words:
spellchecker.indexDictionary(new PlainTextDictionary(new File("myfile.txt")));
String[] suggestions = spellchecker.suggestSimilar("misspelt", 5);
By default, it is using the LevensteinDistance, but you could provide your own customized Edit Distance.
I have a small index with ~1000 documents with only two fields:
- id (string)
- content (text_general)
I noticed that when I do MLT search by id for similar content, the original document(which id is the searched id) have a score 5.241327.
There is 1:1 duplicated document and for the duplicated content it is returning score = 1.5258181. Why? Why it is not 5.241327 when it is 100% duplicate.
Another question is can I in any way to get similarity documents by content by passing some text in the query.
Example:
/mlt/?q=content:Some encoded long text&mlt.fl=content
I am trying to check if there is similar content uploaded and the check must be performed at new content upload time.
It might be worth to try some different parameters. I also use MLT on only one field, I use the following parameters:
'mlt.boost': 'true',
'mlt.fl': 'my_field_name',
'mlt.maxqt': 1000,
'mlt.mindf': '0',
'mlt.mintf': '0',
'qt': 'mlt',
'rows': '10'
See http://wiki.apache.org/solr/MoreLikeThis for an explanation of the parameters. I think with a small index mindf might be important and I see the default mintf (term frequency) is 2, so I assume an ID is only one term, so this is probably ignored!
First, how does Solr More-Like-This works?
A regular Solr query is conducted (e.g. "?q=content:Some encoded long text&.....".
For each document returned by the above query, More-Like-This conduct More like this query...
So, the first result set "response", is just like any Solr query results set.
The More-Like-This appears below and start with something like that (Json format):
"moreLikeThis":{
"57375":{"numFound":18155,"start":0,"docs":["
For an explanation about More Like This algorithm, please read that:
http://blog.brattland.no/node/18
and: http://cephas.net/blog/2008/03/30/how-morelikethis-works-in-lucene/
If you didn't solved the problem yet, please let me know and I will guide you through.