Viewing Slow Query Logs

Scenarios

Slow query logs record statements that exceed the log_min_duration_statement value. You can view log details to identify statements that are slowly executed and optimize the statements.

RDS supports the following statement types:

SELECT
INSERT
UPDATE
DELETE
CREATE
DROP
ALTER
DO
CALL
COPY

Parameter Description

**Table 1** Parameters related to RDS for PostgreSQL slow queries
Parameter	Description
log_min_duration_statement	Specifies how many milliseconds a query has to run before it has to be logged.
log_statement	Specifies the statement type. The value can be none, ddl, mod, or all. The default value is none. If you change the value to all, the database log format changes and slow query logs fail to be parsed.

Viewing Log Details

Log in to the management console.
Click in the upper left corner and select a region and a project.
Click Service List. Under Database, click Relational Database Service. The RDS console is displayed.
On the Instance Management page, click the target DB instance.
In the navigation pane on the left, choose Logs. On the Slow Query Logs page, click Log Details to view details about slow query logs.
- You can view the slow query log records of a specified execution statement type or a specific time period.
- The log_min_duration_statement parameter determines when a slow query log is recorded. However, changes to this parameter do not affect already recorded logs. If log_min_duration_statement is changed from 1,000 ms to 100 ms, none of the previously recorded logs that do not meet the new threshold are deleted. For example, a 1,500 ms SQL statement that was recorded when the threshold was 1,000 ms will not be deleted now that the new threshold is 2,000 ms.

Downloading a Log

Log in to the management console.
Click in the upper left corner and select a region and a project.
Click Service List. Under Database, click Relational Database Service. The RDS console is displayed.
On the Instance Management page, click the target DB instance.
In the navigation pane on the left, choose Logs. On the Slow Query Logs page, click Download. In the log list, locate a log whose status is Preparation completed and click Download in the Operation column.
- The system automatically loads the downloading preparation tasks. The loading duration is determined by the log file size and network environment.
  - When the log is being prepared for download, the log status is Preparing.
  - When the log is ready for download, the log status is Preparation completed.
  - If the preparation for download fails, the log status is Abnormal.
  Logs in the Preparing or Abnormal status cannot be downloaded.
- The download link is valid for 5 minutes. After the download link expires, a message is displayed indicating that the download link has expired. If you need to download the log, click OK.