I can't find any informations on Azure Search documentation about how the results are sorted when the query sent is empty. I've also read the Empty Search section of ElasticSearch but still can't find any answer.
Is this sorting by Key?
Is the backend sending a batch of parallel requests and concatenate the results since the sorting doesn't matter?
in case of empty query, the sort order is unspecified. You cannot rely on any particular order. If you need a specific order, ask for it using orderby query parameter.
HTH,
Eugene
Related
I'm using Solr to run a query on one of our cores. Suppose my documents have two fields: ID, and Name. I also have a separate list of IDs I'm grabbing from a database and passing into the query to boost certain results.
If the document gets returned in the query and the ID is in the list it goes to the top of the results, and if it gets returned in the query and the ID is not in the list then it goes below those that are in the list. The former is from the "boost". My query is something like this -
http://mysolrserver:8983/solr/MyCore/MyQueryHandler?q=Smith&start=0&rows=25&bq=Id%3a(36+OR+76+OR+90+OR+224+OR+391)
I am able to get the boost query working but I need the boosted results to be in alphabetical order by name, then the non boosted results under that also in alphabetical order by name. I need to know what to user for the &sort= parameter.
&sort=score%20desc,Name+asc does not work.
I've looked over a lot of documentation, but I still don't know if this even possible. Any help is appreciated. Thanks!
Solr version is 6.0.1. I am actually using SolrNet to interface with Solr, but I think I can figure out the SolrNet part if I know what the url's &sort= parameter value needs to be.
I figured it out, by doing away with the boost query. I added a sort query using the "exists" function and passing it a sub-query for the ID. The exists returns a boolean value to sort on, then I added the name as a second sort. It works perfect!!
The URL looks like this:
http://mysolrserver:8983/solr/MyCore/MyQueryHandler?q=Smith&start=0&rows=25&sort=exists(query({!v=%27Id:(36+OR+76+OR+90+OR+224+OR+391)%27}))%20DESC,%20Name%20ASC
The closest match to your requirement is the query elevation component[1] .
In your particular case I would first sort my Ids according to my requirements ( sorting them by name for example), then maintain them in the elevate.xml.
At query time you can use the "forceElevation" parameter to force the elevation and then sort the remaining results by name.
[1] https://cwiki.apache.org/confluence/display/solr/The+Query+Elevation+Component
I want to understand how sorting works in GSA in below situations:
1) I am executing the query "Jayesh Bhoyar Autobiography" and I received 2000 records and in the query I have also mentioned sort by Date. So my understanding is GSA will pick Top 1000 records from above list based on the Relevance and then Sort it by Date?
However I want GSA should return only top 100 results for "Jayesh Bhoyar Autobiography" as per the relevance and sort on those top 100 records based on the Date. IS this possible?
If yes, how it is possible?
Regards,
Jayesh Bhoyar
The GSA can't do this by itself. If you want to do this, you can easily build a simple application that fetches the first hundred results sorted by relevance, then sorts those results by date. Use the simple XML API to fetch unformatted results from the GSA.
Search Protocol Reference
I'm performing a multimatch search against an ElasticSearch index, and I want to get back the source object with fields in the same order as they were stored in.
However, when I get the response back from the ElasticSearch query, the fields are in alphabetical order (which is not particularly useful for what I'm doing). I'm fairly confident that it used to behave the desired way in a previous version of ES, but since I upgraded recently it is only returning the fields in alphabetical order.
Edit: Note that if I perform a standard match_all search, then I do get the fields back in the original order. I wonder if it has something to do with the multimatch query?
Edit 2: OK, I just ran it again and it returned the fields in a random order (not alphabetical). Maybe this is a bug in ElasticSearch?
You cannot guarantee any order in what is returned. The source document is a plain old JSON object and by definition:
An object is an unordered set of name/value pairs.
Suppose you have millions items(say search results) and you have different parameters for sorting these items(like in eCommerce sites). We will be showing the items using pagination.
Let us say it can be sorted by date, popularity and relevance and results are paginated. How would you implement this functionality? Generally I would create different compare functions for parameters and get results accordingly.
If there any other efficient way to have this kind of functionality instead of sorting the search results every time? Also, do we generally run sql query every time using relevant order parameter or should we sort the search result of previous query to save us from re-searching time?
"If there any other efficient way to have this kind of functionality instead of sorting the search results every time?"
I would say you do not need sort every time but execute SQL query with appropriate OrderBy parameter, paginate it and show to the user
"Also, do we generally run sql query every time using relevant order parameter or should we sort the search result of previous query to save us from re-searching time?"
For sure you need to generate a new SQL query, as the first page data based on a new order parameter can contain completely different set of data from previouse one.
I got my lucene index with a field that needs to be sorted on.
I have my query and I can make my Sort object.
If I understand right from the javadoc I should be able to do query.SetSort(). But there seems to be no such method...
Sure I'm missing something vital.
Any suggestions?
There are actually two important points. First, the field must be indexed. Second, pass the Sort object into the overloaded search method.
Last time I looked, the docs didn't do a very good job of pointing out the indexing part, and certainly didn't explain why this is so. It took some digging to find out why.
When a field is sortable, the searcher creates an array with one element for each document in the index. It uses information from the term index to populate this array so that it can perform sorting very quickly. If you have a lot of documents, it can use a lot of memory, so don't make a field sortable unless there is a need.
One more caveat: a sortable field must have no more than one value stored in each field. If there are multiple values, Lucene doesn't know which to use as the sort key.
It looks like the actual method you want is e.g. Searcher.search(Query query, Filter filter, int n, Sort sort). setSort is a method of Sort.