Combining index_prefixes and term_vector

[cthibodeau]

Hi

We are trying to speed up our searches and highlightings on ES 6.7.2.

We first activated the term_vector feature with the "with_positions_offsets" value. And it worked fine.

Then we added the "index_prefixes" feature and we got the

java.lang.IllegalArgumentException: cannot index term vector offsets when term vectors are not indexed (field="searchable._index_prefix") error.

Can these two features be used together ? And if so, what is the proper way ?

Thank you

{
    "myField": {
    	"type": "text",
    	"store": true,
    	"fields": {
    	  "searchable": {
    		"type": "text",
    		"term_vector": "with_positions_offsets",
    		"analyzer": "myAnalyzer",
    		"index_prefixes": {
    		  "min_chars": 2,
    		  "max_chars": 8
    		}
    	  }
    	}