I'm using text suggester of elasticsearch. My index contains a document which has a filed name and its value is crick
{
"suggest": {
"my-suggest" : {
"text" : "crick",
"term" : {
"field" : "name",
"sort": "score"
}
}
}
}
it return no match, it only returns a value if there is a misspelled
if I pass the exact text it return nothing any idea !!
You are not using suggest_mode
The suggest mode controls what suggestions are included or controls for what suggest text terms, suggestions should be suggested. Three possible values can be specified:
missing: Only provide suggestions for suggest text terms that are not in the index. This is the default.
popular: Only suggest suggestions that occur in more docs then the original suggest text term.
always: Suggest any matching suggestions based on terms in the suggest text.
Since you haven't mentioned suggest_mode it is picking missing by default.
use this settings
{
"suggest": {
"my-suggest" : {
"text" : "crick",
"term" : {
"field" : "name",
"sort": "score",
"suggest_mode": "always"
}
}
}
}
Related
I'm using Elasticsearch Phrase Suggester for correcting user's misspellings. everything is working as I expected unless user enters a query which it's first letter is misspelled. At this situation phrase suggester returns nothing or returns unexpected results.
My query for suggestion:
{
"suggest": {
"text": "user_query",
"simple_phrase": {
"phrase": {
"field": "title.phrase",,
"collate": {
"query": {
"inlile" : {
"bool": {
"should": [
{ "match": {"title": "{{suggestion}}"}},
{ "match": {"participants": "{{suggestion}}"}}
]
}
}
}
}
}
}
}
}
Example when first letter is misspelled:
"simple_phrase" : [
{
"text" : "گاشانچی",
"offset" : 0,
"length" : 11,
"options" : [ {
"text" : "گارانتی",
"score" : 0.00253151
}]
}
]
Example when fifth letter is misspelled:
"simple_phrase" : [
{
"text" : "کاشاوچی",
"offset" : 0,
"length" : 11,
"options" : [ {
"text" : "کاشانچی",
"score" : 0.1121
},
{
"text" : "کاشانجی",
"score" : 0.0021
},
{
"text" : "کاشنچی",
"score" : 0.0020
}]
}
]
I expect that these two misspelled queries have same suggestions(my expected suggestions are second one). what is wrong?
P.S: I'm using this feature for Persian language.
I have solution for your problem, only need to add some fields in your schema.
P.S: I don't have that much expertise in elasticsearch but I have solved same problem using solr, you can implement same way in elasticSearch too
Create new ngram field and copy all you title name in ngram field.
When you fire any query for missspell word and you get blank result then split
the word and again fire the same query you will get results as expected.
Example : Suppose user searching for word Akshay but type it as Skshay, then
create query in below way you will get results as expected hopefully.
I am here giving you solr example same way you can achieve it using
elasticsearch.
**(ngram:"skshay" OR ngram:"sk" OR ngram:"ks" OR ngram:"sh" OR ngram:"ha" ngram:"ay")**
We have split the word sequence wise and fire query on field ngram.
Hope it will help you.
From Elasticsearch doc:
https://www.elastic.co/guide/en/elasticsearch/reference/6.8/search-suggesters-phrase.html
prefix_length
The number of minimal prefix characters that must match in order be a
candidate suggestions. Defaults to 1. Increasing this number improves
spellcheck performance. Usually misspellings don’t occur in the
beginning of terms. (Old name "prefix_len" is deprecated)
So by default phrase-suggester assumes that the first character is correct because the default value for prefix_length is 1.
Note: setting this value to 0 is not a good way because this will have performance implications.
You need to use the reverse analyzer
I explained it in this post so please go and check my answer
Elasticsearch spell check suggestions even if first letter missed
And regarding the duplicates, you can use
skip_duplicates
Whether duplicate suggestions should be filtered out (defaults to
false).
I'm using a completion suggester in Elasticsearch on a single field. The type contains documents of several users. Is there a way to limit the returned suggestions to documents that match a specific query?
I'm currently using this query:
{
"name" : {
"text" : "Peter",
"completion" : {
"field" : "name_suggest"
}
}
}
Is there a way to combine this query with a different one, e.g.
{
"query":{
"term" : {
"user_id" : "590c5bd2819c3e225c990b48"
}
}
}
Have a look at the context suggester, which is just a specialized completion suggester with filtering capabilities - however this is still not a regular query filter, just keep that in mind.
You can specify both the query and the suggester in your query, like this:
{
"query":{
"term" : {
"user_id" : "590c5bd2819c3e225c990b48"
}
},
"suggest": {
"name" : {
"text" : "Peter",
"completion" : {
"field" : "name_suggest"
}
}
}
}
I have a similar use case, and I've posted my question on elastic search forum, see here
From what I've read so far, I don't think with completion suggester you can limit documents. They essentially create a finite state transducer (prefix tree) at index time, this makes it fast but you lose the flexibility of filtering on additional fields. I don't think context suggester would work in your case (let me know if i am wrong), because the cardinality of user_id is very high.
I think edge-ngrams partial matching is more flexible and might actually work in your use case.
Let me know what you end up implementing.
i am very new to the Elastic search.
Like to know how to search partial multi word search.
\
for ex :
My document
{
"title":"harry porter"
}
i need this document with search with following string
1.)har por
same as sql query (select * from books where title like '%har%' or title like '%por%')
Using a completion suggester will provide most of the feature you want. It will find words starting with an arbitrary string, like "har" or "por".
Check out this question for a full example on how to set up a completion suggester.
As described in the documentation, you can achieve multi-word search (i.e. returning "harry horter" from a search for "por") by creating your analyzer with the option preserve_position_increments set to false
PUT books
{
"mappings": {
"book" : {
"properties" : {
"suggest" : {
"type" : "completion",
"preserve_position_increments": false
},
"title" : {
"type": "keyword"
}
}
}
}
}
Refer to this : Edge NGram Tokenizer
This helps in partial multi-word search (similar to autocomplete suggestions). Hope this helps!
I am using elastic 5.1.1 in my environment. I have chosen completion suggester on a field name post_hashtags with an array of strings to have suggestion on it. I am getting response as below for prefix "inv"
Req:
POST hashtag/_search?pretty&&filter_path=suggest.hash-suggest.options.text,suggest.hash-suggest.options._source
{"_source":["post_hashtags" ],
"suggest": {
"hash-suggest" : {
"prefix" : "inv",
"completion" : {
"field" : "post_hashtags"
}
}
}
Response :
{
"suggest": {
"hash-suggest": [
{
"options": [
{
"text": "invalid",
"_source": {
"post_hashtags": [
"invalid"
]
}
},
{
"text": "invalid",
"_source": {
"post_hashtags": [
"invalid",
"coment_me",
"daya"
]
}
}
]
}
]
}
Here "invalid" is returned twice because it is also a input string for same field "post_hashtags" in other document.
Problems is if same "invalid" input string present in 1000 documents in same index then i would get 1000 duplicated suggestions which is huge and not needed.
Can I apply an aggregation on a field of type completion ?
Is there any way I can get unique suggestion instead of duplicated text field, even though if i have same input string given to a particular field in multiple documents of same index ?
ElasticSearch 6.1 has introduced the skip_duplicates operator. Example usage:
{
"suggest": {
"autocomplete": {
"prefix": "MySearchTerm",
"completion": {
"field": "name",
"skip_duplicates": true
}
}
}
}
Edit: This answer only applies to Elasticsearch 5
No, you cannot de-duplicate suggestion results. The autocomplete suggester is document-oriented in Elasticsearch 5 and will thus return suggestions for all documents that match.
In Elasticsearch 1 and 2, the autocomplete suggester automatically de-duplicated suggestions. There is an open Github ticket to bring back this functionality, and it looks like it is possible to do so in a future version.
For now, you have two options:
Use Elasticsearch version 1 or 2.
Use a different suggestion implementation not based on the autocomplete suggester. The only semi-official suggestion I have seen so far involve putting your suggestion strings in a separate index.
I was working on project to display the matching snippets with its exact locations in the respective document. We are indexing PDF and HTML documents into elastic server. On searching for the text in the indexed documents, first we need to display text around matched text from the document. Then, on clicking this entry, we should bring the document and position at the exact location by highlighting the matched text.
Any help will be highly appreciated.
CM
You can use highlight for highlighting the matched text.
GET /index/type/_search
{
"query" : {
"match_phrase" : {
"field" : "some text"
}
},
"highlight": {
"fields" : {
"field" : {}
}
}
}
You can refer here.