问题
Our team is working on a Postgresql database with lots of tables and views, without any referential constraints. The project is undocumented and there appears to be a great number of unused/temporary/duplicate tables/views dirtying the schema.
We need to discover what database objects have real value and are actually used and accessed. My inital thoughts were to query the Catalog/'data-dictionary'.
Is it possible to query the Postgresql Catalog to find an object's last query time.
Any thoughts, alternative approaches and or tools ideas?
回答1:
Check the Statistics Collector
回答2:
Not sure about the last query time but you can adjust your postgresql.conf to log all SQL:
log_min_duration_statement = 0
That will at least give you an idea of current activity.
回答3:
Reset the statistics, pg_stat_reset(), and then check the pg catalog tables like pg_stat_user_tables and such to see where activity looks like its showing up.
来源：https://stackoverflow.com/questions/3868423/how-to-discover-what-a-postgresql-tables-usage-is