Hi!
Is it possible to perform case insensitive match with phrase suggester? Follow the example in the documentation, if we do
PUT test
{
"settings": {
"index": {
"number_of_shards": 1,
"analysis": {
"analyzer": {
"trigram": {
"type": "custom",
"tokenizer": "standard",
"filter": ["shingle"]
}
},
"filter": {
"shingle": {
"type": "shingle",
"min_shingle_size": 2,
"max_shingle_size": 3
}
}
}
}
},
"mappings": {
"_doc": {
"properties": {
"title": {
"type": "text",
"fields": {
"trigram": {
"type": "text",
"analyzer": "trigram"
}
}
}
}
}
}
}
POST test/_doc?refresh=true
{"title": "noble warriors"}
POST test/_doc?refresh=true
{"title": "Nobel Prize"}
then
POST test/_search
{
"suggest": {
"text": "noble prize",
"simple_phrase": {
"phrase": {
"field": "title.trigram",
"size": 1,
"gram_size": 3,
"direct_generator": [ {
"field": "title.trigram",
"suggest_mode": "always"
} ],
"highlight": {
"pre_tag": "<em>",
"post_tag": "</em>"
}
}
}
}
}
returns nothing.
On the other hand, if we add a lowercase filter to the trigram analyzer
PUT test
{
"settings": {
"index": {
"number_of_shards": 1,
"analysis": {
"analyzer": {
"trigram": {
"type": "custom",
"tokenizer": "standard",
"filter": ["lowercase", "shingle"]
}
},
"filter": {
"shingle": {
"type": "shingle",
"min_shingle_size": 2,
"max_shingle_size": 3
}
}
}
}
},
"mappings": {
"_doc": {
"properties": {
"title": {
"type": "text",
"fields": {
"trigram": {
"type": "text",
"analyzer": "trigram"
}
}
}
}
}
}
}
POST test/_doc?refresh=true
{"title": "noble warriors"}
POST test/_doc?refresh=true
{"title": "Nobel Prize"}
then
POST test/_search
{
"suggest": {
"text": "noble prize",
"simple_phrase": {
"phrase": {
"field": "title.trigram",
"size": 1,
"gram_size": 3,
"direct_generator": [ {
"field": "title.trigram",
"suggest_mode": "always"
} ],
"highlight": {
"pre_tag": "<em>",
"post_tag": "</em>"
}
}
}
}
}
returns nobel prize as suggestion.
My question is: can we combine the best of the two worlds? Is it possible to perform case insensitive match and yet returns the original text?
Thank you 