Apachesolr search result sorting - solr

I'm trying to change sorting from apache Solr query.
for example bundle type: story, videogallery and category_management are indexed.
I wanted to show all results related to bundle type: category_management on top.
See attached screenshot:
Please help me to user Solr filter to sort my result.

The easiest way is to apply a boost to any entry that matches your requirement:
&bq=bundle:category_management^50
The weight - 50 - may have to be adjusted to get the result you want. This is faster than sorting by a function.
This will also still keep relevancy score inside each set of documents, compared to sorting by a function or adding a priority field for sorting.
If you want to actually apply a sort on multiple fields instead, you can first sort by a function that returns 1 for values that match and 0 for values that doesn't. Something like:
sort=if(termfreq(bundle,'category_management'),1,0),ds_changed desc

Related

Display Solr results based on custom selection

I have a filed 'qualification' which is having multiple values (something like MCA, MBA, MSC, PhD, ...).
My requirement is to display results in the order MSC, MCA, PhD, MBA. So, I am using the below query to boost the field values.
&bq=(qualification: "MSC"^5 "MCA"^4 "PhD"^3 "MBA"^2)
The above query is working only when I use q=*:*
But when search with any text like q=course, I am not getting the results with specified order.
Please help what I did wrong.
Thanks & Regards
Venu
You're probably not doing anything "wrong", but when you actually search for something, the score isn't flat (i.e. it's no longer just 1) any more.
If you don't want your query to affect the score, use a filter query (fq instead). This does however not give you any actual relevance inside the results - if you still want that, you'll probably have to adjust your boosts to be far higher, so that the actual scores are only used internally within each boost level.
&bq=qualification:"MSC"^50000
&bq=qualification:"MCA"^40000
&bq=qualification:"PhD"^30000
&bq=qualification:"MBA"^20000
If you append debugQuery=true to your query string, you can see how the score is calculated for each document, and adjust your boosts accordingly.

Sort or filter results by function query defined in a field

I have a Solr 6.2 instance running, and I'm exploring its advantages and limitations. One limitation I've run into seems to be that you can't sort or filter the data based off of a field function query.
.../solr/collection/select?q=*:*&fl=*,total:sum(v1,v2)&fq=total:[10 TO *]
Solr responds with an error stating that the total field does not exist. Indeed, the field is not defined in my schema because it's not a stored part of the dataset - it's calculated at query time. They call it a pseudo field. I haven't been able to find an example in the documentation or a solution online. So, is there a way around this?
.../solr/collection/select?q=*:*&fl=*,total:sum(v1,v2)&fq={!frange l=10} sum(v1,v2)
I have very same problem as you.
I want to query particular division value of two fields.
I tried to used [0.3 TO *] like you.
You can also use upper bound for your range if you need.
http://archive.apache.org/dist/lucene/solr/ref-guide/apache-solr-ref-guide-4.6.pdf
"l" is for lower bound.
"u" is for upper bound.
fq={!frange l=0 u=2.2} sum(user_ranking,editor_ranking)
Maybe this works for you?
you can do this. instead of total try sum.
you can find more info here. https://wiki.apache.org/solr/FunctionQuery#What_is_a_Function.3F
an example from the sole wiki.
Example Function Queries
To give you a better understanding of how function queries can be used in Solr, suppose an index stores the dimensions in meters x,y,z of some hypothetical boxes with arbitrary names stored in field boxname. Suppose we want to search for box matching name findbox but ranked according to volumes of boxes. The query parameters would be:
q=boxname:findbox val:"product(x,y,z)"
This query will rank the results based on volumes. In order to get the computed volume, you will need to request the score, which will contain the resultant volume:
&fl=*, score
Suppose that you also have a field storing the weight of the box as weight. To sort by the density of the box and return the value of the density in score, you would submit the following query:
http://localhost:8983/solr/collection_name/select?q=boxname:findbox val:"div(weight,product(x,y,z))"&fl=boxname x y z weight score`
you can read more about it here. https://cwiki.apache.org/confluence/display/solr/Function+Queries
Try this
solr/collection/select?q=*:* _val_:"sum(v1,v2)"&fl=* score&fq={!frange l=10 }sum(v1,v2)

Sorting by date with AppEngine search API

I have documents with a contents TextField and a date DateField. I am trying to fetch the most recent documents.
A regular search with 'date > epoch' seems to already sort the
results by date. Is that an expected behavior?
When I try to explicitly sort with SortExpression the results are not even sorted in any particular order (except on the dev server where it seems to work as well).
I am using the following code:
index.search(search.Query(query_string='date > epoch',
options=search.QueryOptions(
sort_options=search.SortOptions(
expressions=[search.SortExpression(
expression='date',
direction=search.SortExpression.DESCENDING,
default_value='1970-01-01')])))
What is the right way to do that?
According to the documentation, all documents are sorted by their rank unless you specify a different sorting option. And a document rank is set to the time when it was added to the index, again, unless you specify a different rank.
If this is your desired behavior, there is no need to add a date field and sort by it.
When you filter by a field your are forcing to use index and as side result the output will be sorted by that field.
https://cloud.google.com/appengine/docs/python/search/options
When you call the search() method using a query string alone, the
results are returned according to the default query options:
Documents are returned sorted in order of descending rank
Documents are returned in groups of 20 at a time
Retrieved documents contain all of their original fields
Don't know why it does not work with explicit sorting options.

solr facet counts not correct with stats and group option

I am using solr search for products-search on our web page. Since now, all works fine.
But while implementing a price slider, to filter actual results by pricerange, I'm stuck with the following issue:
There is no way to exclude filters for the stats option, same way as it is possible on facets. I use stats for getting the overall min- and max-price, no matter what price range is selected (on the slider) and which category is selected on actual search.
So best way to get this values is to exclude the range-filter on stats select, otherwise there will be max- and min-price just for the actual (ranged) result.
exclude a filter on facets (works on solr 4.4):
...&fq={!tag=cat}categories:Electronics/Computers&facet=true&facet.field={!ex=cat}categories&...
But using this for stats is not possible (see https://issues.apache.org/jira/browse/SOLR-3177)
So then I tried using a group select as suggested on that called page.
my solr call looks like this:
fq={!tag=cat}categories:Electronics/Computers&facet=true&
facet.field={!ex=cat}categories_raw&
facet.prefix=Electronics&stats=true&stats.field=minPrice&
stats.field=maxPrice&stats.field=vat&group=true&group.query=minPrice:[* TO 20]
maxPrice:[0 TO *]&group.main=true
All fine. I get the correct stats result and the correct result-count having applied the pricerange-filter. .... EXCEPT the problem, that the facet counts now were wrong, as I did not apply the price range filter.
I know there is a group.facet option, as I also tried. But using that group.facet I need to use a group.field on which the results are based on. In my opinion, usually I need to use the price-field as group.field (group.field=price).
But we do have two price fields on our products (min and max-price). I tried to set them both as group.field parameter, but still get the wrong facet-counts.
It looks like I am just a small step away from the correct solution, but I don't get it.

solr sort,i want Specify a particular document at the first

solr sort,i want Specify a particular document at the first
for example:
Results :5,2,3,1
I want 2 at the first ,Other sorted in accordance with the rules
2,1,3,5
how to do this ?
I know of two ways you can try to tackle this using Solr.
The first is to use the QueryElevationComponent. This lets you define the top results at index time. As suggested in the documentation, this is good for placing sponsored results or popular documents at the top of the search results. The potential downside is that you have to be able to identify those documents at index time and not at query time.
The other approach is to boost the desired documents at query time using the bq parameter. To boost document 435, you would do something like this:
...&bq=id:435^10
Unfortunately, neither of these approaches give you absolute control over the order of the results.
The solution provided by Riking would certainly do the job if you don't mind processing the results after performing the search. Another approach you could consider is to add a field to your Solr schema that defines a display order or priority. You can then sort on that field to get the desired sort order.
If you are using Solr 3.1 or later, you can sort by a function query. The map function is useful for this.
sort=map(field_name,5,5,0) asc
In the above, field_name is the name of the field you want to sort by, 5 is the value you want to push to the front and 0 must be replaced with some number that you know is less than all other numbers.
Call the builtin sort() function, then shift the desired element to the front.
Pseudocode, in case you do not have a builtin method to shift it to the front:
tmp = desired;
int dIndex = array.indexOf(desired);
for(i=dIndex-1; i >= 0; i--)
{
array[i+1] = array[i]
}
In case you use standart query (not dismax) add "OR id:2^1000" to you query. Like this:
q=(text:lalala AND author:Bob) OR id:2^1000
that will place document with ID=2 at the top of results.

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