elasticsearch - is there a way to boost matches in long documents in elasticsearch

Question

In elasticsearch the length of the document matters a lot to the final score of the search results. So if I have a match in a field that is just one line long, its going to score much higher than a single match in say .... a document with 5 pages of text. Is there a way to override this behavior, or reliably and repeatedly boost the result to overcome this behavior?

Answer 1

I guess you mean that the length of the matching field is taken into account when computing the score. If you want to just disable this behaviour you can omit norms while indexing. That way you would lose index time boosting as well, but I guess you're not using it and even if you need boosting you should use query time boosting, way more flexible.

You have to update the mapping for your field like this:

"field_name" : {
    "type" : "string",
     "omit_norms" : true
}

If you want to override this default behaviour for all your string fields you can use a dynamic template like this:

{
    "type_name" : {
        "dynamic_templates" : [
            {
                "omit_norms_template" : {
                    "match_mapping_type" : "string",
                    "mapping" : {
                        "omit_norms" : true
                    }
                }
            }
        ]
    }
}