my_indexr: Script to drop and recreate MySQL indexes

Sunday, January 12th, 2014

As can be read in this article, I was in need of a method to quickly drop all indexes (except primary keys) from a MySQL database. After googling around a bit and being astonished that apparently no-one had written such a thing yet, I wrote the script that can be seen in that article.

Unfortunately, that script wasn’t very good, so I decided to do a cleaner better implementation of it. The result is my_indexr, which spits out SQL commands to drop and recreate indexes on a database. Other features include:

• Process only certain tables
• Process non-primary or both normal and primary indexes
• Correctly handles:
  • Primary key indexes
  • Compound key / multi-column indexes
  • Index types (BTREE, etc)
  • Prefix lengths
  • Auto_increment columns, which MUST be a key (my_indexr skips indexes with these columns in them)

There may still be some edge-cases that are not properly handled by my_indexr. If you encouter one, please let me know.

You can download my_indexr from its Bitbucket page.

This is what its output looks like:

$ ./indexr.py -u root -p mydb
DROP INDEX `location` ON `idx_tst_innodb_basic`;
DROP INDEX `name_age` ON `idx_tst_innodb_basic`;
DROP INDEX `email` ON `idx_tst_innodb_basic`;
DROP INDEX `PRIMARY` ON `idx_tst_innodb_compkey`;
CREATE  INDEX `location` USING BTREE ON `idx_tst_innodb_basic` (`location_id`);
CREATE  INDEX `name_age` USING BTREE ON `idx_tst_innodb_basic` (`name`(40),`age`);
CREATE UNIQUE INDEX `email` USING BTREE ON `idx_tst_innodb_basic` (`email`);
ALTER TABLE `idx_tst_innodb_compkey` ADD PRIMARY KEY (`last_name`,`first_name`);