Query is blocked for [min]

What is this alert?

If a query that has started to execute is blocked by another query for the specified number of minutes, Command Center raises an alert.

Queries that are queued, but have not yet started, do not trigger this alert.

Alert details

The alert contains the Query ID, database name and user, and run-time details.

Qid":{“Tmid”:1541113373,“Ssid”:6968,“Ccnt”:3},“Database”:“postgres”,“User”:“gpmon”,“SubmitTime”:“2018 -11-02T16:10:04+08:00”,“StartTime”:“2018-11-02T16:10:04+08:00”,“QueryText”:“”}

Need alert type specific JSON example to write this out

What to do

  1. Use the Query Monitor to locate the blocked query and the query that blocks it.

  2. Determine whether the blocking query is executing properly:

- Is the query also blocked? 
- Is the query blocking a large number of other queries?
- Is the query creating excessive spill files?
- Is the query running in the correct resource group or resource queue? 
- Is the query running longer than usual?
- Does the query have excessive data or CPU skew?
  1. Determine whether you should allow the query to complete, or cancel the query so that the blocked queries can resume.