PostgreSQL High Availability Cookbook - Second Edition

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Growth rates are also important. We recommend that you create a scheduled task that checks these results at the end of every day and either e-mails them to you or saves them into a table for further examination. After statistics are checked and logged, call these two functions to reset them to zero:

SELECT pg_stat_statements_reset();
SELECT pg_stat_reset();

Any tables that are growing quickly are even more critical to identify early.