I have the following simple query in solr in which I want to solr all the records based on their name similarity to a text ("Olive Tasting Room"):
query: name:"Olive Tasting Room"
But when I search it on solr it returns only one document which is most similar. this is while I want a sorted list of all my documents based on their rank (similarity to my query).
how should I do this in sorl/lucene ?
When you use the `field:"Term Term2" syntax, you're doing a phrase search - i.e. you expect the terms to come in succession after each other.
The best way to handle more "natural" queries is to use the edismax query parser. You do this by using defType=edismax in the URL. After changing to edismax, you can enter the query itself in q - q=Olive Tasting Room (escape it properly if you enter it directly into an URL), and qf=name (qf is short for "query fields", which fields the edismax handler should query).
You can also use the pf3=text parameter to give a boost to any documents that feature three words from your query after each other (and pf2 for just two) in the text.
Related
I am using Solr (with pySolr) to search products in my database, returning products, facets and facet.pivots:
result = solr.search(query_s, **{
'rows': '24',
'sort': formatted_sort,
'facet': 'on',
'facet.limit': '-1',
'facet.mincount': '1',
'facet.field': ['gender', 'material'],
'facet.pivot': 'brand,series',
'fq': '-in_stock:(0 OR 99 OR 100 OR 101)'
})
The query_s selects specific fields, for example: brand:Target AND gender:Men's.
I would like to combine the above query with a DisMax query which will allow me to combine the above query with a full text search over specified fields. I found an article which demonstrates nested queries. I have tried to implement something like this:
q: "gender:* AND _query_:"{!edismax qf=brand series}Summer""
For some reason 'Target' will return results for Target brand shirts, but only with correct capitalization. 'Summer' which is a series of Target, won't return any results. Why am I not seeing a list of docs ordered by relevancy?
Am I overcomplicating things by using Dismax altogether?
The dismax parsers are useful for making sense of more "natural" queries, i.e. queries where the user is used to just type what they're looking for, and how most search engines work.
In your case it sounds like brand:Target AND gender:Men's are filters for which documents should be shown, while the query is the part that the user has typed. Usually you'll want to have the filters in fq as they don't affect score (i.e. they're exact values matching a field value), and the query in q.
I assume that Summer is what the user would have typed into your search box, which would give you:
q=Summer&defType=edismax&qf=series
But this assumes that the series field is defined as a text field that has an analyzer attached, so that the values are lowercased and split appropriately.
If you also have a description field you'd like to search, you can do:
q=Summer&defType=edismax&qf=series^20 description
.. which would search for Summer in both the series and description fields, but give 20 times more weight to a hit in the series field. This is a good way to naturally boost documents that match more exact data in your documents. If you also include the brand field, you'd be able to let your users search for "target summer" and similar queries.
I'm looking into the possibility of de-boosting a set of documents during
query time. In my application, when I search for e.g. "preferences", I want
to de-boost content tagged with ContentGroup:"Developer" or in other words,
push those content back in the order. Here's the catch. I've the following
weights on query fields and boost query on source
qf=text^6 title^15 IndexTerm^8
As you can see, title has a higher weight.
Now, a bunch of content tagged with ContentGroup:"Developer" consists of a
title like "Preferences.material" or "Preferences Property" or
"Preferences.graphics". The boost on title pushes these documents at the
top.
What I'm looking is to see if there's a way to deboost all documents that are
tagged with ContentGroup:"Developer" irrespective of the term occurrence is
text or title. I tried something like, but didn't make any difference.
Source:simplecontent^10 Source:Help^20 (-ContentGroup-local:("Developer"))^99
I'm using edismax query parser.
Any pointers will be appreciated.
Thanks,
Shamik
You're onto something with your last attempt, but you have to start with *:*, so that you actually have something to subtract the documents from. The resulting set of documents (those not matching your query) can then be boosted.
From the Solr Relevancy FAQ
How do I give a negative (or very low) boost to documents that match a query?
True negative boosts are not supported, but you can use a very "low" numeric boost value on query clauses. In general the problem that confuses people is that a "low" boost is still a boost, it can only improve the score of documents that match. For example, if you want to find all docs matching "foo" or "bar" but penalize the scores of documents matching "xxx" you might be tempted to try...
q = foo^100 bar^100 xxx^0.00001 # NOT WHAT YOU WANT
...but this will still help a document matching all three clauses score higher then a document matching only the first two. One way to fake a "negative boost" is to give a large boost to everything that does not match. For example...
q = foo^100 bar^100 (*:* -xxx)^999
NOTE: When using (e)dismax, people sometimes expect that specifying a pure negative query with a large boost in the "bq" param will work (since Solr automatically makes top level purely negative positive queries by adding an implicit ":" -- but this doesn't work with "bq", because of how queries specified via "bq" are added directly to the main query. You need to be explicit...
?defType=dismax&q=foo bar&bq=(*:* -xxx)^999
I am creating a front end application which queries through a database using the Apache Solr engine, but I have two issues that I just cannot find the answer to.
When Solr is processing a Facet query, how do I get the facet to be a single phrase ("Department of the Navy (160)") instead of a broken up facet of 4 terms ("Department (160)" "of (200)" "the (200)" "Navy(160)").
Also, how do I remove certain facets from being queried, for example "and" "to" "the" etc.
Thank you.
Looks like your phrase is being indexed into a Text field which, among many things, splits by whitespace. This is very good for full text search but not for faceting.
You can have a duplicate field for this, of type string (and not Text), which is not splitted. You can still use the original field for searching but the new string field for faceting.
We're working on a plan to identify content tags our users are interested in. So, for instance, we may determine that User X consumes content tagged with "kermit" and "piggy" more often than other tags. These are their "favored tags."
When the users search, we'd like to favor/bias documents that contain these terms.
This means we can't boost the documents at index time, because every user will have different favored tags. Additionally, they may not be searching for the favored tags themselves. They may search for "gonzo," and so we absolutely want to give them documents with "gonzo," but we want to boost documents that also contain "kermit" or "piggy."
These favored tags are not used to actually query the index, but rather are used to bias the result ordering. The favored tags become something of a tie-breaker -- all else being equal, documents containing these terms will rank higher.
This is new/planned development, so we can use whatever version and parser stack is optimal to solve this problem.
Solution in SolrNet
The question was correctly answered below, but here's the code for SolrNet just in case someone else is using it.
var localParams = new LocalParams();
localParams.Add("bq", "kermit^10000); //numeric value is the degree of boost
var solr = ServiceLocator.Current.GetInstance<ISolrOperations<MySolrDocumentClass>>();
solr.Query(new SolrQuery("whatever") + localParams);
You didn't specify which query parser you're using, but if you are using the Dismax or Extended Dismax query parser, the bq argument should do exactly what you're looking for. bq adds search criteria to a search solely for the purpose of affecting the relevancy, but not to limit the result set.
From the Dismax documentation:
The bq (Boost Query) Parameter
The bq parameter specifies an additional, optional, query clause that
will be added to the user's main query to influence the score. For
example, if you wanted to add a relevancy boost for recent documents:
q=cheese
bq=date:[NOW/DAY-1YEAR TO NOW/DAY]
You can specify multiple bq parameters. If you want your query to be
parsed as separate clauses with separate boosts, use multiple bq
parameters.
In this case, you may want to add &bq=kermit&bq=piggy to the end of your Solr query. If you aren't using one of these query parsers, this need may be exactly the motivation you need to switch.
I'm doing a "More Like This" query on 3 text fields, but I'd like to also boost the results based on a numeric "views" field. In a normal query I'd add a boost term like "{!boost b=scale(sqrt(views),1,2)}" or something similar, but this doesn't seem to work if I specify it in the mlt.qf field. Is formula based boosting allowed in MLT queries?
According to the More Like This page on the Solr Wiki, the mlt.qf field allows for boosts.
Query fields and their boosts using the same format as that used in DisMaxQParserPlugin. These fields must also be specified in mlt.fl.
Checkout the syntax for boosting with the DisMaxQParserPlugin and you should be able to get the boosting you desire.
Also, check out the answer to this previous question - Is it possible to boost mlt queries in Solr