num_changes()

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

Early access Since 1.6.0

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

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

Arguments

The syntax is:

num_changes(
    summary GaugeSummary
) RETURNS BIGINT

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

Returns

Column	Type	Description
num_changes	BIGINT	The number of times the gauge changed