MySQL 8 Cookbook

pt-duplicate-key-checker

pt-duplicate-key-checker gives the exact ALTER statements to drop duplicate keys:

shell> pt-duplicate-key-checker -u <user> -p<pass># A software update is available:# ######################################################################### employees.employees                                                     # ######################################################################### full_name_1 is a duplicate of full_name# Key definitions:#   KEY `full_name_1` (`first_name`,`last_name`),#   KEY `full_name` (`first_name`,`last_name`),# Column types:#      `first_name` varchar(14) not null#      `last_name` varchar(16) not null# To remove this duplicate index, execute:ALTER TABLE `employees`.`employees` DROP INDEX `full_name_1`;# first_name is a left-prefix of full_name# Key definitions: ...