Github user nvazquez commented on the pull request:

    https://github.com/apache/cloudstack/pull/1466#issuecomment-207994438
  
    @bhaisaab Most of the indexes being dropped are duplicate. In 
create-schema.sql quite a lot of tables are created like this:
    CREATE TABLE `cloud`.`version` (
    `id` bigint unsigned NOT NULL UNIQUE AUTO_INCREMENT COMMENT 'id',
    `version` char(40) NOT NULL UNIQUE COMMENT 'version',
    `updated` datetime NOT NULL COMMENT 'Date this version table was updated',
    `step` char(32) NOT NULL COMMENT 'Step in the upgrade to this version',
    PRIMARY KEY (`id`),
    INDEX `i_version__version`(`version`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    
    When column ID is marked as UNIQUE MySQL creates an unique index ID. Then 
below a primary key ID is defined. Primary key in its nature already guarantees 
uniqueness so it is safe to drop index ID leaving only primary key to remain.
    There are more than 50 tables like this plus 3 more tables where unique 
index based on ID column was created twice. For example for domain_router table 
one duplicate index was created initially in create-schema.sql and another 
duplicate was generated in schema-442to450.sql when the following line was 
executed:
    ALTER TABLE `cloud`.`domain_router` MODIFY `id` bigint unsigned 
AUTO_INCREMENT UNIQUE NOT NULL;


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---

Reply via email to