Logging slow statements
In this recipe, we will be discussing how to track the slow running SQL statements.
Getting ready
In any database management system, checking the database logs is a regular action by the developers/DBA to find the root cause, for any database related issues. PostgreSQL provides various log settings, which controls its logger process. By using proper logging settings, we can control the amount of log messages, and the format of the log content. In some cases, having proper logging settings will help in debugging the situations as mentioned here.
Sometimes, it is not an easy job to figure out why a query is running very slowly, as there could be many reasons behind the slowness of the execution. The reasons could be:
Concurrent locks on the same table
Volume of the data
Bad execution plan for the query and so on
As we discussed previously, if you have proper logging settings, PostgreSQL will log some useful information such as query duration, process ID, client host details...
