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Query with Data Statistics¶

Description¶

Elastic Search is the underlying search engine that CM-Well uses when performing a query (which involves a full-text search on infoton field values). Elastic Search supports several types of statistical metrics of field values within a given group of infotons. For example, using statistical features, you can discover how many distinct values there are for a certain field in a certain group of infotons. (The Elastic Search statistical feature is called "aggregations", and you may see some references to this term in the search syntax and results.)

CM-Well passes the statistical query to Elastic Search, which performs the analysis and returns its results, which are passed back to the caller. You can learn more about Elastic Search aggregation options here.

Note

You can use all the regular CM-Well query parameters such as qp, recursive, date filters and so on, before applying a statistical query. The statistical analysis is applied on the subset of the data that passes the filters.

Syntax¶

URL: <hostURL>/<PATH>

REST verb: GET

Mandatory parameters: op=stats&ap=type:<statsType>,field:<statsField>

Template:

<cmwellPath>?op=stats&ap=type:<statsType>,field:<statsField>,name:<outputName>&format=<outputFormat>

URL example:

<cm-well-host>/permid.org?op=stats&ap=type:card,name:MyCurrencyStats,field:iso4217.currency&format=json&pretty

Curl example (REST API):

Curl -X GET "<cm-well-host>/permid.org?op=stats&ap=type:card,name:MyCurrencyStats,field:iso4217.currency&format=json&pretty"

Special Parameters¶

Parameter	Description	Values	Example
ap	Aggregation parameters that define the statistical query type and field.	See below in this table.
type	The type of statistical query to perform. See Using Elastic Search Statistics to learn more.	card, stats, term, sig	ap=type:card
name	Optional. If supplied, its value is returned as the name value in the response.	Any string	ap=name:MyQueryName
field	The name of the field on whose values you want to apply the query.	Any valid CM-Well field name	ap=field:CommonName.mdaas

Code Example¶

Call¶

curl "<cm-well-host>/permid.org?op=stats&ap=type:card,name:MyCurrencyStats,field:iso4217.currency&format=json&pretty"

Results¶

{
      "AggregationResponse" : [ {
        "name" : "MyCurrencyStats",
        "type" : "CardinalityAggregationResponse",
        "filter" : {
            "name" : "MyCurrencyStats",
            "type" : "CardinalityAggregation",
            "field" : "iso4217.currency"
        },
        "count" : 266
      } ]
    }