Postgres Source - No value for count query equal to 0

Grafana Time Series Panel
1

Hi,

I want to have a Graph panel in Series mode to show the number of tasks completed and not completed.

Here’s my query:

SELECT
  $__timeGroup(time_col,'1m') as time,
  count(col_to_count)
FROM
  my_table
WHERE
  col_status= 'N' and $__timeFilter(time_col)
GROUP BY time

When the count is equal to 0, nothing is shown in the graph, even if I put the display null value to 0.
For the query with the ‘Y’ value (Completed tasks), it works.

How can I make it work? (I’m using Grafana 4.6.3)

Thanks,

2

You need to return data for every interval of your time group to get proper counts.

The easiest way to achieve that is joining against a generate_series query that returns a value for every time group.

You need something similar to https://github.com/grafana/grafana/issues/10073

There is a pull request to add this functionality directly to grafana but it has not been merged yet: https://github.com/grafana/grafana/pull/10138

3

Ok, I understand the issue.

I will wait the fix :wink: