I found this in https://wiki.postgresql.org/wiki/Todo :
Improve ability to display optimizer analysis using OPTIMIZER_DEBUG What does this actually mean? Add GUC switch to enable optimizer debug on/off? More fancy/useful info should be printed? If so, what kind of information is required? -- Tatsuo Ishii SRA OSS, Inc. Japan English: http://www.sraoss.co.jp/index_en.php Japanese: http://www.sraoss.co.jp -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
