How to include Std dev in Legends of time series?

Grafana Configuration
1

I am new to grafana and I have the latest version (8.4.3). I created a panel using Time Series and I am able to include max, min, mean and so on in the legends. Along with that, I want to include Std dev and how can I do?

2

welcome to the :grafana: forum, @selvavm

I don’t think standard deviation is a possible legend value in Grafana. That might make a good feature request.

What datasource are you using? You could always try to calculate standard deviation on the DB side. I think influx has a stddev() function…`

3

Thanks mattabrams. My database supports it but I am not able to find how to do add this to the legend? Is there a way?

4

you can’t add it to the legend in the same way as the other built-in legend items

5

Sorry for late response. I met with unfortunate events.

Could you tell me how can I visualise the standard deviation from my db? For example, I can write below queries

select t, events from from pingtable

select min(events), stddev(events) from pingtable
6

Please provide your sample data as csv as follows and the visualization you want to use?

id,report_date,area,team,volumne
3,2022-04-18,area1,B,26

or basic DDL and DML

create table areas(id nt, report_date datetime, 
area varchar(50), team, char(1), volume int)

insert into areas
values(3,'2022-04-18','area1','B',26)
7

Hi below is the details

create table pingtable(hit_date datetime, 
events int, browser char(1))

insert into pingtable
values('2022-04-18','10', 'E');
insert into pingtable
values('2022-04-19','5', 'E');
insert into pingtable
values('2022-04-20','15', 'E');

I would like to plot the timeseries and in legends (or somewhere) see the standard deviation as 4.08.

1 Like
8

option 1
create a hidden dashboard variable named standarddev with

SELECT  STDEVP(events) as value FROM pingtable

Then for you data source query do

SELECT
 $__timeEpoch(hit_date),
 events as value,
 events metric,
 $standarddev deviation
FROM pingtable 
ORDER BY hit_date ASC

results in (painful on the eyes) with using Legend Mode/Legend Values of Last

image
image1168×514 53.3 KB

9

option 2 (best option) as it can also scale cleanly with more values.
one time series with gauge or stat (both use sql statement
SELECT STDEVP(events) as value FROM pingtable
)

image
image1136×510 106 KB

10

Thanks. I have repeating panels to plot different columns based on user selection. If I want to get this, then I believe I will have to change the repeating panels to repeating rows. Am I right?

Also, I could see that a query is hit per panel. So if I have 5 panels, 5 queries are hit. So, in this case, it will be 10 queries per row. Is there a way to optimise the counts of queries.

11

this sounds like a totally new question unrelated to std dev? If so maybe create a new topic?

12

thanks. Will do that.