Sam 29fac1ac18 PERF: improve performance of unread queries ... Figuring out what unread topics a user has is a very expensive operation over time. Users can easily accumulate 10s of thousands of tracking state rows (1 for every topic they ever visit) When figuring out what a user has that is unread we need to join the tracking state records to the topic table. This can very quickly lead to cases where you need to scan through the entire topic table. This commit optimises it so we always keep track of the "first" date a user has unread topics. Then we can easily filter out all earlier topics from the join. We use pg functions, instead of nested queries here to assist the planner.		2017-05-25 15:07:30 -04:00
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fixtures	fix deploy problems due to renamed table	2017-05-12 15:17:25 -04:00
migrate	PERF: improve performance of unread queries	2017-05-25 15:07:30 -04:00
api_test_seeds.rb	add rake task and seed data for discourse_api	2014-09-10 20:53:21 -06:00