<story><title>How to Read MySQL EXPLAINs</title><url>https://planetscale.com/blog/how-read-mysql-explains</url></story><parent_chain></parent_chain><comment><author>denton-scratch</author><text>My first experience with Oracle (this was a long time ago, and I suspect they didn&amp;#x27;t even call it EXPLAIN). Anyway, I found it significantly better and clearer than the EXPLAIN output from Postgres or MySQL.&lt;p&gt;There was a query being emitted by the anti-fraud software of a certain well-known US bank, that was taking 45 minutes to run, which didn&amp;#x27;t please the fraud team. This fraud team weren&amp;#x27;t highly-paid elites; they were drudge workers, as much at risk of burnout as anyone.&lt;p&gt;Anyway, I was tasked with fixing this (low-importance) problem. I managed to figure out what the problem was with the query, with the help of EXPLAIN. I reconstructed the query so it ran in less than 10 seconds, and submitted the patch.&lt;p&gt;It took two months for the DBAs to let me add the requisite index to production. They&amp;#x27;d given me a copy of the production database, eventually, so I could test my change, and make sure it didn&amp;#x27;t break anything else; but they still held it back. DBAs were very anally-retentive in those days.&lt;p&gt;I got no credit for that (except from myself :-). I&amp;#x27;m happy to pat myself on the back for reducing the query time from absurd to reasonable, and by a factor of 1&amp;#x2F;270.&lt;p&gt;I&amp;#x27;ve never used Oracle since, by the way; it&amp;#x27;s always looked to me like a blind alley. But $FINCORP used to like Oracle, and the Oracle DBAs were treated like ghodz.</text></comment>
<story><title>How to Read MySQL EXPLAINs</title><url>https://planetscale.com/blog/how-read-mysql-explains</url></story><parent_chain></parent_chain><comment><author>SeanA208</author><text>What&amp;#x27;s the best resource for the equivalent of this page but for Postgres?</text></comment>