I’ve recently run into a situation where I could not perform online alter table operations to modify the type of one column from tinyint(3) unsigned to int(10) unsigned using the pt-online-schema-change without specifying --nocheck-plan since the table has a multi-column primary key. I believe that there should be no problem with this operation, but I am a bit wary of specifying --nocheck-plan in a production environment since the docs do not make it clear what sort of risks are involved.
Could somebody inform me what risks I face by specifying --no-checkplan when using the pt-online-schema-change tool? Specifically, I want to know if there is any potential risk of data loss.
Thanks a bunch,