Join transform for time series

  • What Grafana version and what operating system are you using?
    OS Grafana 10.1.0, 10.1.1

  • What are you trying to achieve?

Mixed data source.

  1. MS SQL query returns time-series data “time”, “metric-id”, “value”
  2. PG SQL query returns table data “metric-id”, “metric”

Aim - visualize time series as
MS-SQL.“time”
PG-SQL.“metric” (multiple keys)
MS-SQL.“value”

  • How are you trying to achieve it?

Using mixed data source I’m making two queries (MSSQL + PGSQL) that return data as above.

  1. Applying transform “Join by field”.INNER by “metric-id”
  2. Applying transform “Filter by name”.metric-id

These transforms leaves me with a three desired columns, namely MS-SQL.“time”, PG-SQL.“metric”, MS-SQL.“value”.
But to my greatest sorrow it only works is MS-SQL query Format is set to Table.
If it is a Table format - time-series visualization doesn’t work.
If it is a Time series format - transformation doesn’t work correctly.

Referring to transformed data from another panel as a “Dashboard” data source has no effect.

Am I doing anything wrong?