metrics

An array of MetricDataQuery structures that enable you to create an alarm based on the result of a metric math expression. For each PutMetricAlarm operation, you must specify either MetricName or a Metrics array.

Each item in the Metrics array either retrieves a metric or performs a math expression.

One item in the Metrics array is the expression that the alarm watches. You designate this expression by setting ReturnData to true for this object in the array. For more information, see MetricDataQuery.

If you use the Metrics parameter, you cannot include the Namespace, MetricName, Dimensions, Period, Unit, Statistic, or ExtendedStatistic parameters of PutMetricAlarm in the same operation. Instead, you retrieve the metrics you are using in your math expression as part of the Metrics array.