When MySQL needs to sort its output rows, and cannot do this via indexes, it uses a quicksort function called filesort(). This does not necessarily mean it will touch the disk at any time.
I'm working on a event tracking system which uses a handful of lookup tables as well as the primary logging …
mysql optimization select temporary filesortI have a simple mysql query, but when I have a lot of records (currently 103,0000), the performance is really slow …
mysql performance database-performance filesortOn a simple but very large Innodb table, I have a unique index on column A and I want to …
mysql sql-order-by innodb filesortI'm planning on creating a view using this SQL SELECT, but the explain for it shows it's using temporary and …
mysql explain filesortI need your help to optimize the query to avoid using "Using filesort".The job of the query is to …
mysql performance optimization query-optimization filesortI'm trying to optimize this query: SELECT `posts`.* FROM `posts` INNER JOIN `posts_tags` ON `posts`.id = `posts_tags`.post_…
mysql optimization join sql-order-by filesortLet's suppose I have the following table (let's call it my_table): CREATE TABLE `my_table` ( `table_id` int(10) unsigned …
sql mysql performance filesort