From b30b932447d3ae059c0dac2c5bf0a3a79e0fa54e Mon Sep 17 00:00:00 2001 From: Xavier Noria Date: Fri, 25 Nov 2011 14:58:43 -0800 Subject: finders guide: adds some pointers to help users interpret the output of EXPLAIN --- railties/guides/source/active_record_querying.textile | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'railties/guides') diff --git a/railties/guides/source/active_record_querying.textile b/railties/guides/source/active_record_querying.textile index 0f1f6eba4c..c4724f182e 100644 --- a/railties/guides/source/active_record_querying.textile +++ b/railties/guides/source/active_record_querying.textile @@ -1344,3 +1344,14 @@ EXPLAIN for: SELECT `posts`.* FROM `posts` WHERE `posts`.`user_id` IN (1) under MySQL. + +h4. Interpreting EXPLAIN + +Interpretation of the output of EXPLAIN is beyond the scope of this guide. The +following pointers may be helpful: + +* SQLite3: "EXPLAIN QUERY PLAN":http://www.sqlite.org/eqp.html + +* MySQL: "EXPLAIN Output Format":http://dev.mysql.com/doc/refman/5.6/en/explain-output.html + +* PostgreSQL: "Using EXPLAIN":http://www.postgresql.org/docs/current/static/using-explain.html -- cgit v1.2.3