"order by" taking too much time in mysql

Question

"order by" in a query takes a lot of time in MySQL. SHOW PROFILES indicates that the time is being executed by the sorting process. Is there a setup / workaround that will reduce the sorting time?

Answer 1

If you do not have an index in the field that you order, add it:

"In some cases, MySQL may use the index to execute the ORDER BY clause without additional sorting.

Edit: (From the section on optimizing ORDER BY in the MySQL documentation.)

Answer 2

Adding the appropriate indexes for the fields you order should do the trick.

Answer 3

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Answer 4

ALTER TABLE `tablename` ADD INDEX `indexname` (`columnname`);

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Answer 5

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Answer 6

: show create table tbl_name " "

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