devdocs/specs/core-performance.txt

@@ -6,6 +6,15 @@ http://okigiveup.net/what-postgresql-tells-you-about-its-performance/
 
 
 Useful queries to indicate how indexes are being used in postgresql
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+OK: this is the best query to use to find non used indexes
+Run it and look for any indexes that are *not* primary keys (name ends in pkey, want ones that end in idx which are mine)
+that have zero in idx_scan, that means they are completely unused (if a lot of full test runs that excercise all routes and features have happened prior to checking)
+
+SELECT * FROM pg_stat_user_indexes order by idx_scan asc
+
+Following queries might be useful but for different purposes...
 
 This is a test query I used with widget and name fetching performance analysis:
 explain analyze SELECT m.name