Create a metric

Define a set of time based metrics that are generated using captured and stored streamed events

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Metrics are defined as individual units referred to as a metric family. A metric family is an SQL query that defines metric calculations computed within a continuous scheduled cycle, making them available to all processors.

Metrics Definition

This example configures a list of metrics to be computed. One or more metric families can be configured, each there own management policies.

Example

foreach metric compute:
  metrics:
    - name: BidMovingAverage
      metric key: symbol
      table definition: standardQuoteAnalyticsStream.BidMovingAverage (symbol VARCHAR, avg_bid_min FLOAT, avg_bid_avg FLOAT,avg_bid_max FLOAT)
      query:
        SELECT symbol,
          MIN(bid) AS 'avg_bid_min',
          AVG(bid) AS 'avg_bid_avg',
          MAX(bid) AS 'avg_bid_max'
        FROM standardQuoteAnalyticsStream.quote
        WHERE
          ingestTime >= date_trunc('minutes',now() - INTERVAL 2 MINUTES) AND ingestTime <= date_trunc('minutes',now())
        GROUP BY symbol
        ORDER BY 1;
      truncate on start: true
      compaction policy:
        frequency: 8
        time unit: HOURS

Metric attributes

Each metric is defined using the below metrics.

Attribute	Description	Data Type	Required
name	Unique metric family name	String
metric key	Unique key for the metric to be used to optimise query generation and processing	String
query	Metrics ANSI SQL query, See DuckDB SQL documentation	String
table definition	SQL table definition for the resulting metrics	String
truncate on start	Truncate metric data on restart. Note if you import metrics using the initialisation DSL element you will need to set this to false.	Boolean Default: true
compaction policy	Compact the table	See compaction policy

Compaction policy

Compacts the metric table by deleting all row less than the max createdTimestamp

Attribute	Description	Data Type	Required
frequency	Frequency to execute compaction processing. Default is set to 1.	Long
time units	Time unit frequency is define as. Default is set to HOURS. Support unit MINUTES and HOURS	String
compaction query	User defined compaction query	String