elasticsearchHow do I use an elasticsearch query filter?

An Elasticsearch query filter is used to filter the search results of a query using a specific criteria. This can be done by adding a filter clause to the query.

For example, to filter a query for documents with a field name equal to John:

GET /_search
{
  "query": {
    "bool": {
      "filter": {
        "term": {
          "name": "John"
        }
      }
    }
  }
}

This query will return documents that match the filter criteria, in this case documents with the field name equal to John.

The filter clause can also be used to filter on multiple criteria. For example, to filter documents with a field name equal to John and a field age greater than 30:

GET /_search
{
  "query": {
    "bool": {
      "filter": [
        {
          "term": {
            "name": "John"
          }
        },
        {
          "range": {
            "age": {
              "gt": 30
            }
          }
        }
      ]
    }
  }
}

This query will return documents that match both filter criteria, in this case documents with the field name equal to John and the field age greater than 30.

The filter clause can also be used to filter on multiple criteria using logical operators. For example, to filter documents with a field name equal to John or a field age greater than 30:

GET /_search
{
  "query": {
    "bool": {
      "filter": [
        {
          "term": {
            "name": "John"
          }
        },
        {
          "range": {
            "age": {
              "gt": 30
            }
          }
        }
      ],
      "should": [
        {
          "term": {
            "name": "John"
          }
        },
        {
          "range": {
            "age": {
              "gt": 30
            }
          }
        }
      ]
    }
  }
}

This query will return documents that match either filter criteria, in this case documents with the field name equal to John or the field age greater than 30.

Helpful links

• Elasticsearch Query DSL
• Elasticsearch Filters

Edit this code on GitHub