ElasticSearch query with not contains

0
votes

I'm writing a Java application and use elastic search as database.

I'm looking for a way to write a "not-contains" query.

For Example I've got a field category with values:

  • Car
  • Bus
  • Train
  • Fastcar

Now I want to get all entries which not contains "fast" in their category.

How can I build a query like this? I have been looking around here but can't find anything.

Thanks in advance

So thanks to @James and @Bhavya Gupta I could update my query but it doesn't work as expected.

My query now is:

"query": {
        "bool": {
            "must": {
                "match_all": {}
            },
            "filter": {
                "bool": {
                    "must_not": [
                        {
                            "term": {
                                "BetriebsID": "Aufzug"
                            }
                        }   ]
                    }
                }
        }
    }

But the result still contains hits like this:

"hits": [
            "_source": {
                ...
                "FormNo": 9150520000000692,
                "CreatedTime": "2020-05-15T08:19:03.000Z",
                "templateId": "Aufzugsstoerung",
                "SYS_FORM_ID": "150520_000000692",
                "trecId": 151,
                "BetriebsID": "20200515_1019_Aufzugsstoerung",
                "displayName": "Aufzugsstörung",
                ...
            }
            }]

I also tried it with the wildcard query from James, with the same result.

2
javaelasticsearch
did you get a chance to go through my answer, looking forward to get feedback from you :) – ESCoder
yes I did but i doesn't work for me. I updated my question. Please have a look. – dominic
so I get the query to work. The error was, there is a keyword-mapping on BetriebsId. So I need to filter for BetriebsId.keyword. Than the query works as expected – dominic

2 Answers

1
votes

You can make use of Boolean Queries with must_not for the same. Kibana query would look like:

GET my_index/_search
{
  "query": {
    "bool": {
      "must_not": [
        {
          "wildcard": {
            "category": {
              "value": "fast*"
            }
          }
        }
      ]
    }
  }
}

Sample Java Code:

        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder()
                .query(QueryBuilders.boolQuery().mustNot(QueryBuilders.wildcardQuery("category", "fast*")));
        SearchRequest searchRequest = new SearchRequest("index_name");
        searchRequest.source(searchSourceBuilder);
        SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
1
votes

Wildcard queries can also be used as suggested by @James, but it is not recommended to use Wildcard (especially at the beginning of search query), as it may affect the performance and slow down the search.

Adding a working example with index mapping, search query, and search result

Index Mapping:

{
    "settings": {
        "analysis": {
            "analyzer": {
                "my_analyzer": {
                    "tokenizer": "my_tokenizer"
                }
            },
            "tokenizer": {
                "my_tokenizer": {
                    "type": "ngram",
                    "min_gram": 2,
                    "max_gram": 10,
                    "token_chars": [
                        "letter",
                        "digit"
                    ]
                }
            }
        },
        "max_ngram_diff": 50
    },
    "mappings": {
        "properties": {
            "category": {
                "type": "text",
                "analyzer": "my_analyzer",
                "search_analyzer": "standard"
            }
        }
    }
}

Search Query:

{
    "query": {
        "bool": {
            "must": {
                "match_all": {}
            },
            "filter": {
                "bool": {
                    "must_not": [
                        {
                            "term": {
                                "category": "fast"
                            }
                        }
                    ]
                }
            }
        }
    }
}

Search Result:

"hits": [
      {
        "_index": "stof_64009221",
        "_type": "_doc",
        "_id": "1",
        "_score": 1.0,
        "_source": {
          "category": "car"
        }
      },
      {
        "_index": "stof_64009221",
        "_type": "_doc",
        "_id": "2",
        "_score": 1.0,
        "_source": {
          "category": "bus"
        }
      },
      {
        "_index": "stof_64009221",
        "_type": "_doc",
        "_id": "3",
        "_score": 1.0,
        "_source": {
          "category": "train"
        }
      }
    ]