WARNING: Version 5.x has passed its EOL date.

This documentation is no longer being maintained and may be removed. If you are running this version, we strongly advise you to upgrade. For the latest information, see the current release documentation.

« Significant Terms Aggregation Usage Pipeline Aggregations »

› › ›

Terms Aggregation Usage

edit

Terms Aggregation Usage

edit

A multi-bucket value source based aggregation where buckets are dynamically built - one per unique value.

See the Elasticsearch documentation on terms aggregation for more detail.

Fluent DSL example

edit

s => s
.Size(0)
.Aggregations(a => a
    .Terms("states", st => st
        .Field(p => p.State)
        .MinimumDocumentCount(2)
        .Size(5)
        .ShardSize(100)
        .ExecutionHint(TermsAggregationExecutionHint.Map)
        .Missing("n/a")
        .Script(ss => ss.Inline("'State of Being: '+_value").Lang("groovy"))
        .Order(TermsOrder.TermAscending)
        .Order(TermsOrder.CountDescending)
        .Meta(m => m
            .Add("foo", "bar")
        )
    )
)

Object Initializer syntax example

edit

new SearchRequest<Project>
{
    Size = 0,
    Aggregations = new TermsAggregation("states")
    {
        Field = Field<Project>(p => p.State),
        MinimumDocumentCount = 2,
        Size = 5,
        ShardSize = 100,
        ExecutionHint = TermsAggregationExecutionHint.Map,
        Missing = "n/a",
        Script = new InlineScript("'State of Being: '+_value") { Lang = "groovy" },
        Order = new List<TermsOrder>
        {
            TermsOrder.TermAscending,
            TermsOrder.CountDescending
        },
        Meta = new Dictionary<string, object>
        {
            { "foo", "bar" }
        }
    }
}

Example json output.

{
  "size": 0,
  "aggs": {
    "states": {
      "meta": {
        "foo": "bar"
      },
      "terms": {
        "field": "state",
        "min_doc_count": 2,
        "size": 5,
        "shard_size": 100,
        "execution_hint": "map",
        "missing": "n/a",
        "script": {
          "inline": "'State of Being: '+_value",
          "lang": "groovy"
        },
        "order": [
          {
            "_term": "asc"
          },
          {
            "_count": "desc"
          }
        ]
      }
    }
  }
}

Handling Responses

edit

response.ShouldBeValid();
var states = response.Aggs.Terms("states");
states.Should().NotBeNull();
states.DocCountErrorUpperBound.Should().HaveValue();
states.SumOtherDocCount.Should().HaveValue();
states.Buckets.Should().NotBeNull();
states.Buckets.Count.Should().BeGreaterThan(0);
foreach (var item in states.Buckets)
{
    item.Key.Should().NotBeNullOrEmpty();
    item.DocCount.Should().BeGreaterOrEqualTo(1);
}
states.Meta.Should().NotBeNull().And.HaveCount(1);
states.Meta["foo"].Should().Be("bar");

Filtering with a regular expression pattern

edit

Using terms aggregation with filtering to include values using a regular expression pattern

Fluent DSL example

edit

s => s
.Size(0)
.Aggregations(a => a
    .Terms("states", st => st
        .Field(p => p.State.Suffix("keyword"))
        .MinimumDocumentCount(2)
        .Size(5)
        .ShardSize(100)
        .ExecutionHint(TermsAggregationExecutionHint.Map)
        .Missing("n/a")
        .Include("(Stable|VeryActive)")
        .Order(TermsOrder.TermAscending)
        .Order(TermsOrder.CountDescending)
        .Meta(m => m
            .Add("foo", "bar")
        )
    )
)

Object Initializer syntax example

edit

new SearchRequest<Project>
{
    Size = 0,
    Aggregations = new TermsAggregation("states")
    {
        Field = Field<Project>(p => p.State.Suffix("keyword")),
        MinimumDocumentCount = 2,
        Size = 5,
        ShardSize = 100,
        ExecutionHint = TermsAggregationExecutionHint.Map,
        Missing = "n/a",
        Include = new TermsIncludeExclude { Pattern = "(Stable|VeryActive)" },
        Order = new List<TermsOrder>
        {
            TermsOrder.TermAscending,
            TermsOrder.CountDescending
        },
        Meta = new Dictionary<string, object>
        {
            { "foo", "bar" }
        }
    }
}

Example json output.

{
  "size": 0,
  "aggs": {
    "states": {
      "meta": {
        "foo": "bar"
      },
      "terms": {
        "field": "state.keyword",
        "min_doc_count": 2,
        "size": 5,
        "shard_size": 100,
        "execution_hint": "map",
        "missing": "n/a",
        "include": "(Stable|VeryActive)",
        "order": [
          {
            "_term": "asc"
          },
          {
            "_count": "desc"
          }
        ]
      }
    }
  }
}

Handling Responses

edit

response.ShouldBeValid();
var states = response.Aggs.Terms("states");
states.Should().NotBeNull();
states.DocCountErrorUpperBound.Should().HaveValue();
states.SumOtherDocCount.Should().HaveValue();
states.Buckets.Should().NotBeNull();
states.Buckets.Count.Should().BeGreaterThan(0);
foreach (var item in states.Buckets)
{
    item.Key.Should().NotBeNullOrEmpty();
    item.DocCount.Should().BeGreaterOrEqualTo(1);
}
states.Meta.Should().NotBeNull().And.HaveCount(1);
states.Meta["foo"].Should().Be("bar");

Filtering with exact values

edit

Using terms aggregation with filtering to include only specific values

Fluent DSL example

edit

s => s
.Size(0)
.Aggregations(a => a
    .Terms("states", st => st
        .Field(p => p.State.Suffix("keyword"))
        .MinimumDocumentCount(2)
        .Size(5)
        .ShardSize(100)
        .ExecutionHint(TermsAggregationExecutionHint.Map)
        .Missing("n/a")
        .Include(new[] { StateOfBeing.Stable.ToString(), StateOfBeing.VeryActive.ToString() })
        .Order(TermsOrder.TermAscending)
        .Order(TermsOrder.CountDescending)
        .Meta(m => m
            .Add("foo", "bar")
        )
    )
)

Object Initializer syntax example

edit

new SearchRequest<Project>
{
    Size = 0,
    Aggregations = new TermsAggregation("states")
    {
        Field = Field<Project>(p => p.State.Suffix("keyword")),
        MinimumDocumentCount = 2,
        Size = 5,
        ShardSize = 100,
        ExecutionHint = TermsAggregationExecutionHint.Map,
        Missing = "n/a",
        Include = new TermsIncludeExclude { Values = new[] { StateOfBeing.Stable.ToString(), StateOfBeing.VeryActive.ToString() } },
        Order = new List<TermsOrder>
        {
            TermsOrder.TermAscending,
            TermsOrder.CountDescending
        },
        Meta = new Dictionary<string, object>
        {
            { "foo", "bar" }
        }
    }
}

Example json output.

{
  "size": 0,
  "aggs": {
    "states": {
      "meta": {
        "foo": "bar"
      },
      "terms": {
        "field": "state.keyword",
        "min_doc_count": 2,
        "size": 5,
        "shard_size": 100,
        "execution_hint": "map",
        "missing": "n/a",
        "include": [
          "Stable",
          "VeryActive"
        ],
        "order": [
          {
            "_term": "asc"
          },
          {
            "_count": "desc"
          }
        ]
      }
    }
  }
}

Handling Responses

edit

response.ShouldBeValid();
var states = response.Aggs.Terms("states");
states.Should().NotBeNull();
states.DocCountErrorUpperBound.Should().HaveValue();
states.SumOtherDocCount.Should().HaveValue();
states.Buckets.Should().NotBeNull();
states.Buckets.Count.Should().BeGreaterThan(0);
foreach (var item in states.Buckets)
{
    item.Key.Should().NotBeNullOrEmpty();
    item.DocCount.Should().BeGreaterOrEqualTo(1);
}
states.Meta.Should().NotBeNull().And.HaveCount(1);
states.Meta["foo"].Should().Be("bar");

Filtering with partitions

edit

A terms aggregation that uses partitioning to filter the terms that are returned in the response. Further terms can be returned by issuing additional requests with an incrementing partition number.

Partitioning is available only in Elasticsearch 5.2.0+

Fluent DSL example

edit

s => s
.Size(0)
.Aggregations(a => a
    .Terms("commits", st => st
        .Field(p => p.NumberOfCommits)
        .Include(0, 10)
        .Size(5)
    )
)

Object Initializer syntax example

edit

new SearchRequest<Project>
{
    Size = 0,
    Aggregations = new TermsAggregation("commits")
    {
        Field = Field<Project>(p => p.NumberOfCommits),
        Include = new TermsIncludeExclude
        {
            Partition = 0,
            NumberOfPartitions = 10
        },
        Size = 5
    }
}

Example json output.

{
  "size": 0,
  "aggs": {
    "commits": {
      "terms": {
        "field": "numberOfCommits",
        "size": 5,
        "include": {
          "partition": 0,
          "num_partitions": 10
        }
      }
    }
  }
}

Handling Responses

edit

response.ShouldBeValid();
var commits = response.Aggs.Terms<int>("commits");
commits.Should().NotBeNull();
commits.DocCountErrorUpperBound.Should().HaveValue();
commits.SumOtherDocCount.Should().HaveValue();
commits.Buckets.Should().NotBeNull();
commits.Buckets.Count.Should().BeGreaterThan(0);
foreach (var item in commits.Buckets)
{
    item.Key.Should().BeGreaterThan(0);
    item.DocCount.Should().BeGreaterOrEqualTo(1);
}

Numeric fields

edit

A terms aggregation on a numeric field

Fluent DSL example

edit

s => s
.Size(0)
.Aggregations(a => a
    .Terms("commits", st => st
        .Field(p => p.NumberOfCommits)
        .ShowTermDocCountError()
    )
)

Object Initializer syntax example

edit

new SearchRequest<Project>
{
    Size = 0,
    Aggregations = new TermsAggregation("commits")
    {
        Field = Field<Project>(p => p.NumberOfCommits),
        ShowTermDocCountError = true
    }
}

Example json output.

{
  "size": 0,
  "aggs": {
    "commits": {
      "terms": {
        "field": "numberOfCommits",
        "show_term_doc_count_error": true
      }
    }
  }
}

Handling Responses

edit

response.ShouldBeValid();
var commits = response.Aggs.Terms<int>("commits");
commits.Should().NotBeNull();
commits.DocCountErrorUpperBound.Should().HaveValue();
commits.SumOtherDocCount.Should().HaveValue();
commits.Buckets.Should().NotBeNull();
commits.Buckets.Count.Should().BeGreaterThan(0);
foreach (var item in commits.Buckets)
{
    item.Key.Should().BeGreaterThan(0);
    item.DocCount.Should().BeGreaterOrEqualTo(1);
}
commits.Buckets.Should().Contain(b => b.DocCountErrorUpperBound.HasValue);

« Significant Terms Aggregation Usage Pipeline Aggregations »