PostgreSQL auto_explain Extension: Optimizing Query Performance in PostgreSQL 16

PostgreSQL Auto_Explain_Extension

To use the advanced auto_explain extension in PostgreSQL 16, you should first load it into the server. This can be done by adding auto_explain to either session_preload_libraries or shared_preload_libraries in the postgresql.conf file. This setup allows you to track slow queries as they occur. The auto_explain module has several configurable parameters:

• auto_explain.log_min_duration: Sets the minimum execution time for a statement to have its plan logged.
• auto_explain.log_analyze: Enables the logging of EXPLAIN ANALYZE output.
• auto_explain.log_buffers and auto_explain.log_wal: Control the logging of buffer and WAL usage statistics.
• auto_explain.log_timing: Toggles the logging of per-node timing information.
• auto_explain.log_triggers: Includes trigger execution statistics in logs.
• auto_explain.log_verbose: Enables verbose output.
• auto_explain.log_settings: Logs information about modified configuration options.
• auto_explain.log_format: Sets the output format (text, xml, json, yaml).
• auto_explain.log_level: Determines the log level for the query plan.
• auto_explain.log_nested_statements: Controls whether nested statements are logged.
• auto_explain.sample_rate: Sets the fraction of statements to explain in each session.

For example, to log every query with its execution plan, you can set auto_explain.log_min_duration to 0 and enable auto_explain.log_analyze. Remember, enabling some of these features, especially auto_explain.log_analyze, can impact performance due to the overhead of collecting detailed statistics. For detailed information and examples, please refer to the PostgreSQL 16 documentation on auto_explain.