STL_RETURN
Contains details for return steps in queries. A return step returns the results of queries completed on the compute nodes to the leader node. The leader node then merges the data and returns the results to the requesting client. For queries completed on the leader node, a return step returns results to the client.
A query consists of multiple segments, and each segment consists of one or more steps. For more information, see Query processing.
STL_RETURN is visible to all users. Superusers can see all rows; regular users can see only their own data. For more information, see Visibility of data in system tables and views.
Note
STL_RETURN only contains queries run on main provisioned clusters. It doesn't contain queries run on concurrency scaling clusters or on serverless namespaces. To access explain plans for queries run on both main clusters, concurrency scaling clusters, and serverless namespaces, we recommend that you use the SYS monitoring view SYS_QUERY_DETAIL . The data in the SYS monitoring view is formatted to be easier to use and understand.
Table columns
| Column name | Data type | Description |
|---|---|---|
| userid | integer | ID of the user who generated the entry. |
| query | integer | Query ID. The query column can be used to join other system tables and views. |
| slice | integer | Number that identifies the slice where the query was running. |
| segment | integer | Number that identifies the query segment. |
| step | integer | Query step that ran. |
| starttime | timestamp | Time in UTC that the query started. Total time includes queuing and execution. with 6 digits of precision for fractional seconds. For example: 2009-06-12 11:29:19.131358. |
| endtime | timestamp | Time in UTC that the query finished. Total time includes queuing and execution. with 6 digits of precision for fractional seconds. For example: 2009-06-12 11:29:19.131358. |
| tasknum | integer | Number of the query task process that was assigned to run the step. |
| rows | bigint | Total number of rows that were processed. |
| bytes | bigint | Size, in bytes, of all the output rows for the step. |
| packets | integer | Total number of packets sent over the network. |
| checksum | bigint | This information is for internal use only. |
Sample queries
The following query shows which steps in the most recent query were performed on each slice.
SELECT query, slice, segment, step, endtime, rows, packets from stl_return where query = pg_last_query_id(); query | slice | segment | step | endtime | rows | packets -------+--------+---------+------+----------------------------+------+--------- 4 | 2 | 3 | 2 | 2013-12-27 01:43:21.469043 | 3 | 0 4 | 3 | 3 | 2 | 2013-12-27 01:43:21.473321 | 0 | 0 4 | 0 | 3 | 2 | 2013-12-27 01:43:21.469118 | 2 | 0 4 | 1 | 3 | 2 | 2013-12-27 01:43:21.474196 | 0 | 0 4 | 4 | 3 | 2 | 2013-12-27 01:43:21.47704 | 2 | 0 4 | 5 | 3 | 2 | 2013-12-27 01:43:21.478593 | 0 | 0 4 | 12811| 4 | 1 | 2013-12-27 01:43:21.480755 | 0 | 0 (7 rows)
