One of the nice features of ElasticSearch is the support for 'stemming’. Stemming brings a word back to its root. For example a search on skis or skiing will both match results with ski. Typically you still want to support search operations on the original word by applying a multi-field approach where you index both the stemmed values and the original value:
| .AutoMap() | |
| .Properties(pps => pps | |
| .Text(pg=> pg | |
| .Name(p=> p.ProductName) | |
| .Analyzer("english-analyzer") | |
| .Fields(f => f | |
| .Keyword(p => p.Name("raw"))// Index raw value as well to support sorting and exact match searches | |
| ) | |
| ) |
But now you need to know if your user is searching for an exact match(e.g. a search for ski should only return results where the original value was ski) or stemmed results. Fortunately, the query_string and simple_query_string queries have a feature that solve this exact problem: quote_field_suffix. This tell Elasticsearch that the words that appear in between quotes are to be redirected to a different field, see below:
| .QueryString(qs => qs | |
| .Query(form.Query) | |
| .QuoteFieldSuffix(".raw") | |
| ) |
Now if ski is in-between quotes, it issearched on the productName.raw field due to the quote_field_suffix parameter.