The Query Monitor view allows you to view detailed information for active queries running on the Greenplum Database system. Superusers and users assigned the operator role can see and cancel all users’ queries.
Data is collected on currently running queries and the query monitor metrics are updated every 15 seconds. The time of the last update and a graphical timer showing the time remaining before the next update are displayed at the top of the page.
With the information available on this tab, Greenplum Database administrators can easily:
- Understand how the system is being used — both in real-time and trending over time.
- Identify and diagnose problem queries while they are running, detect skew, find runaway queries, and so on.
- Review and balance the query load on the system by better optimizing and scheduling the query load.
- Cancel queries that disrupt system performance.
The Query Monitor table displays the following columns for queries.
ccntfields. (See queries_* in the Command Center Database Reference.)
- Queued: the query has not yet started to execute
- Running: execution has started, is not yet complete
- Done: completed successfully
- Cancelling: cancel request sent, cancel pending
- Cancelled: terminated, no longer running
Using the Query Monitor Controls
Click a column heading to sort the rows on that column in ascending or descending order.
Click the checkbox at the left of a row to choose a query to cancel or export. Click the checkbox in the heading row to choose all queries.
Click Cancel Query to cancel selected queries.
Click Export to download a comma-separated values (CSV) text file containing rows for the selected queries. When no queries are selected, all rows are exported. The default file name is
Click any query ID to see the Query Details, including metrics, the text of the query, and the query plan.