Class::DBI::Loader::mysql (along with Class::DBI::mysql) provide MySQL specific over-rides for the inspection of the DB schema that is necessary for Class::DBI::Loader to do what it does: for the most part you shouldn't need to concern yourself with the documentation for the DB specific modules as Class::DBI::Loader does the right thing for the most part. But no they are not standalone alternatives, and Class::DBI::Loader::msyql will be installed as part of the Class::DBI::Loader installation.
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