Tomas Vondra-4 wrote > Hello Sergei, > >> This patch correlates with my proposal >> "add session information column to pg_stat_statements" >> https://www.postgresql.org/message-id/3aa097d7-7c47-187b-5913-db8366cd4491%40gmail.com >> They both address the problem to identify the factors that make >> different execution plans for the same SQL statements. You are >> interested in the current settings that affect the execution plan, I'm >> concerned about historical data in pg_stat_statements. From my >> experience the most often offending settings are >> current_schemas/search_path and current_user. Please have in mind that >> probably the same approach that you will use to extend explain plan >> functionality will be eventually implemented to extend >> pg_stat_statements. > > Possibly, although I don't have an ambition to export the GUCs into > pg_stat_statements in this patch. There's an issue with merging > different values of GUCs in different executions of a statement, and > it's unclear how to solve that. > > [...] > > -- > Tomas Vondra http://www.2ndQuadrant.com > PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
This explain with GUCs feature can be included very easily for historical data management in pg_store_plans or pg_stat_sql_plans extensions (that both use a planid based on the normalized plan text). Regards PAscal -- Sent from: http://www.postgresql-archive.org/PostgreSQL-hackers-f1928748.html
