influxdb.cardinality() function
influxdb.cardinality()
returns the series cardinality of data retrieved from InfluxDB.
Although this function is similar to InfluxQL’s SHOW SERIES CARDINALITY
,
it works in a slightly different manner.
influxdb.cardinality()
is time bounded and reports the cardinality of data that matches the conditions passed into it rather than that of the bucket as a whole.
Function type signature
(
start: A,
?bucket: string,
?bucketID: string,
?host: string,
?org: string,
?orgID: string,
?predicate: (r: {B with _value: C, _measurement: string, _field: string}) => bool,
?stop: D,
?token: string,
) => stream[{_value: int, _stop: time, _start: time}] where A: Timeable, D: Timeable
Parameters
bucket
Bucket to query cardinality from.
bucketID
String-encoded bucket ID to query cardinality from.
org
Organization name.
orgID
String-encoded organization ID.
host
URL of the InfluxDB instance to query.
See InfluxDB Cloud regions or InfluxDB OSS URLs.
token
InfluxDB API token.
start
(Required) Earliest time to include when calculating cardinality.
The cardinality calculation includes points that match the specified start time.
Use a relative duration or absolute time. For example, -1h
or 2019-08-28T22:00:00Z
.
Durations are relative to now()
.
stop
Latest time to include when calculating cardinality.
The cardinality calculation excludes points that match the specified start time.
Use a relative duration or absolute time. For example, -1h
or 2019-08-28T22:00:00Z
.
Durations are relative to now()
. Default is now()
.
The default value is now()
, so any points that have been written into the future will
not be counted unless a future stop
date is provided.
predicate
Predicate function that filters records.
Default is (r) => true
.
Examples
- Query series cardinality in a bucket
- Query series cardinality in a measurement//
- Query series cardinality for a specific tag
- Query series cardinality of Data Written In the Last 4 Hours
Query series cardinality in a bucket
import "influxdata/influxdb"
influxdb.cardinality(bucket: "example-bucket", start: time(v: 1))
Note: if points have been written into the future, you will need to add an appropriate stop
date
Query series cardinality in a measurement//
import "influxdata/influxdb"
influxdb.cardinality(
bucket: "example-bucket",
start: time(v: 1),
predicate: (r) => r._measurement == "example-measurement",
)
Query series cardinality for a specific tag
import "influxdata/influxdb"
influxdb.cardinality(bucket: "example-bucket", start: time(v: 1), predicate: (r) => r.exampleTag == "foo")
Query Cardinality of Data Written In the Last 4 hours
import "influxdata/influxdb"
influxdb.cardinality(bucket: "example-bucket", start: -4h)
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