I am using BooleanFilter for performing filter in lucene index.
code:
BooleanFilter _filter = new BooleanFilter();
var locationFilter = new TermsFilter();
locationFilter.AddTerm(new Term("Location", "Dhaka"));
_filter.Add(new FilterClause(locationFilter, Occur.MUST));
And in my Search code snippet
var hits = searcher.Search(query, _filter, hits_limit, Sort.RELEVANCE).ScoreDocs;
This code works fine;
But sometimes i don't need to filter with location then i just put a empty BooleanFilter and perform search like this:
BooleanFilter _filter = new BooleanFilter();
var hits = searcher.Search(query, _filter, hits_limit, Sort.RELEVANCE).ScoreDocs;
Now why do hits not return me no search result?;
I think that your empty BooleanFilter is matching nothing..
Try using the other overload of search search(Query query, int n, Sort sort)
Related
When I try to search text in a file,I wonder if I could get the results searched by vscode.Is there some api that I can use?
I found some functions like TextSearchProvider in vscode proposed api,but this api is used to search text in whole workplace.I just want the result searched in one file.
example picture
For example,When I try to search Selection,I want the result of this search.
Some code from my extension Find and Transform:
function _findAndSelect(editor, findValue, restrictFind) {
let foundSelections = [];
// get all the matches in the document
let fullText = editor.document.getText();
let matches = [...fullText.matchAll(new RegExp(findValue, "gm"))];
matches.forEach((match, index) => {
let startPos = editor.document.positionAt(match.index);
let endPos = editor.document.positionAt(match.index + match[0].length);
foundSelections[index] = new vscode.Selection(startPos, endPos);
});
editor.selections = foundSelections; // this will remove all the original selections
}
Just get the text of the current document, do some string search like matchAll using your search term. In the code above I wanted to select all those matches in the document - you may or may not be interested in that.
It looks like you want your search term to be the current selection:
// editor is the vscode.window.activeTextEditor
let selection = editor.selection;
let selectedRange = new vscode.Range(selection.start, selection.end);
let selectedText = editor.document.getText(selectedRange);
For some reason I am unable to use Select() after a Skip()/Take() unless I do this in a certain way. The following code works and allows me to use result as part of a sub query.
var query = QueryOver.Of<MyType>();
query.Skip(1);
var result = query.Select(myType => myType.Id);
However, if I attempt to create the query on one line as below I can't compile.
var query = QueryOver.Of<MyType>().Skip(1);
var result = query.Select(myType => myType.Id);
It looks like the code in the first results in query being of type QueryOver< MyType, MyType> while the second results in query being of type QueryOver< MyType>.
It also works if written like this.
var query = QueryOver.Of<MyType>().Select(myType => myType.Id).Skip(1);
Any ideas why the second version fails horribly when the first and third versions work? It seems like odd behavior.
You have a typo in the second version...
var query = QueryOver.Of<MyType().Skip(1);
is missing the >
var query = QueryOver.Of<MyType>().Skip(1);
Not sure if thats what you where looking for.
I’m actually using Lucene 2.9.4.1 and everything works just fine if I search for something that exists just once in the same line.
Per instance, if Lucene find the same string that I’m looking for in the same line, I have duplicated (or more) results.
I’m actually using the following BooleanQuery:
booleanQuery.Add(new TermQuery(new Term(propertyInfo.Name, textSearch)), BooleanClause.Occur.SHOULD);
The second issue is about searching by something with spaces like “hello world”: never works.
Can anyone advise me or help me with these two malfunctioning features, please?
Thank you so much in advance,
Best regards,
Well, I just found the answer that solved both of my issues =)
I was using this:
BooleanQuery booleanQuery = new BooleanQuery();
PropertyInfo[] propertyInfos = typeof(T).GetProperties();
foreach (PropertyInfo propertyInfo in propertyInfos)
{
booleanQuery.Add(new TermQuery(new Term(propertyInfo.Name, textSearch)), BooleanClause.Occur.SHOULD);
}
And now I use this:
var booleanQuery = new BooleanQuery();
textSearch = QueryParser.Escape(textSearch.Trim().ToLower());
string[] properties = typeof(T).GetProperties().Select(x => x.Name).ToArray();
Analyzer analyzer = new StandardAnalyzer(global::Lucene.Net.Util.Version.LUCENE_29);
MultiFieldQueryParser titleParser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_29, properties, analyzer);
Query titleQuery = titleParser.Parse(textSearch);
booleanQuery.Add(titleQuery, BooleanClause.Occur.SHOULD);
It seems that Analyzer and MultiFieldQueryParser are the solution for my problems: no more duplicated results, I can search by something with spaces and … the performance as significantly raised up (faster results) =)
I was writing a search for one of our sites: (SITE A)
BooleanQuery booleanQuery = new BooleanQuery();
foreach (var field in fields)
{
QueryParser qp = new QueryParser(field, new StandardAnalyzer());
Query query = qp.Parse(search.ToLower() + "*");
if (field.Contains("Title")) { query.SetBoost((float)1.8); }
booleanQuery.Add(query, BooleanClause.Occur.SHOULD);
}
// CODE DIFFERENCE IS HERE
Query query2 = new TermQuery(new Term("StateProperties.IsActive", "True"));
booleanQuery.Add(query2, BooleanClause.Occur.MUST);
// END CODE DIFFERENCE
Lucene.Net.Search.TopScoreDocCollector collector = Lucene.Net.Search.TopScoreDocCollector.create(21, true);
searcher.Search(booleanQuery, collector);
hits = collector.TopDocs().scoreDocs;
this was working as expected.
since we own a few sites, and they use the same skeleton,
i uploaded the search to another site ( SITE B )
but the search stopped returning results.
after playing a round a bit with the code, i managed to make it work like so: (showing only the rewriten lines of code)
QueryParser qp2 = new QueryParser("StateProperties.IsActive", new StandardAnalyzer());
Query query2 = qp2.Parse("True");
booleanQuery.Add(query2, BooleanClause.Occur.MUST);
anyone knows why this is happening ?
i have checked the Lucene dll version, and its the same version in both sites (2.9.2.2)
is the code i have written in SITE A wrong ? is SITE B code wrong ?
is this my fault at all ? can production server infulance something like this ?
Doesn't they have individual indexes on disk? If they have been indexed differently, they would also return different results. One thing that comes to mind is if there is some sort of case sensitivity that matters, becayse a TermQuery will look for an EXACT match, where as the parser will try to tokenize/filter the search term according to the analyzer (and probably search for "true" instead of "True".
I am doing a search operation by using lucene where i was taking my results by using topscorecollector, but i found that it unable to sort my topscorecollector results. I found it quiet odd to sort that. Can we sort the TopscoreCollector results?
My code looks like this
TopScoreDocCollector collector = TopScoreDocCollector.create(100, true);
indexSearch.Search(andSearchQuery, filter, collector);
ScoreDoc[] hits = collector.TopDocs().scoreDocs;
for (int i = 0; i < hits.Length; i++)
{
int docId = hits[i].doc;
float score = hits[i].score;
Lucene.Net.Documents.Document doc = indexSearch.Doc(docId);
document.Add(doc);
}
Can anybody help me?
Also one more doubt
we can sort the search results like this
Hits hits = IndexSearch.search(searchQuery, filter, sort);
But it is showing that Hits become obselete by Lucene 3.0. so i have opted for TopscoreCollector. But now iam very much confused?
If anyother alternate method for Hits, Please pass that to me...
TopScoreDocCollector will return results sorted by score. To get results sorted on a field you will need to use a method overload that returns TopFieldDocs.
IE: IndexSearcher.Search(query, filter, nResults, sort)
If you dont want to limit the number of results use a very large value for the nResults parameter. If i remember correctly passing Int32.MAX_VALUE will make Lucene generate an exception when initializing its PriorityQueue but Int32.MAX_VALUE-1 is fine.