corr()

The correlation coefficient of the least squares fit line of the adjusted counter value and epoch value of the time column. Given that the slope of a line for any counter value must be non-negative, this must also always be non-negative and in the range from 0.0 to 1.0. It measures how well the least squares fit the available data, where a value of 1.0 represents the strongest correlation between time and the counter increasing.

2. corr(

4. summary CounterSummary

6. ) RETURNS DOUBLE PRECISION

For more information about counter aggregation functions, see the hyperfunctions documentation.

Required arguments

Name Type Description
summary CounterSummary The input CounterSummary from a counter_agg call

Returns

Name Type Description
corr DOUBLE PRECISION The correlation coefficient computed from the least squares fit of the adjusted counter values input to the CounterSummary

Sample usage

2. SELECT

4. id,

6. bucket,

8. corr(summary)

10. FROM (

12. SELECT

14. id,

16. time_bucket('15 min'::interval, ts) AS bucket,

18. counter_agg(ts, val) AS summary

20. FROM foo

22. GROUP BY id, time_bucket('15 min'::interval, ts)

24. ) t