num_changes()

Get the number of times a gauge changed from a gauge aggregate

Early access 1.6.0

Get the number of times the gauge changed during the period summarized by the gauge aggregate.

Arguments

Name	Type	Default	Required	Description
summary	GaugeSummary	-	✔	A gauge summary created using gauge_agg

Returns

BIGINT: The number of times the gauge changed

Samples

Get the number of times the gauge changed over each 15-minute interval.

SELECT
    id,
    bucket,
    num_changes(summary)
FROM (
    SELECT
        id,
        time_bucket('15 min'::interval, ts) AS bucket,
        gauge_agg(ts, val) AS summary
    FROM foo
    GROUP BY id, time_bucket('15 min'::interval, ts)
) t