phpMyAdmin on your live site should solve your problem. Before you migrate the database from your local site, make copies of the _comments and _commentmeta tables on your live site. You can do that in phpMyAdmin by selecting your database, then clicking the Operations tab and using the “structure and data” and “drop table” options in the “copy table” section. Let’s say you copy _comments to _csave and _commentmeta to _cmetasave. Then migrate the database. After the migration is complete, copy _csave to _comments and _cmetasave to _commentmeta using the same procedure/options as above. You should repeat this process every time you want to do a migration.
Note that I left off the table prefix in the table names. If the table prefix in wp_config.php is “wp_”, then the tables names would be, for example, wp_comments and wp_csave.
This procedure assumes your migration application doesn’t drop, then re-create the database. It would be pretty stupid for the application to do that, but if you think it’s possible, make a backup of your entire live database before you do the above for the first time.
I hate local development servers…
Sounds like such a great idea but some wind up being such a very different environment that migrating makes little sense. Often the dev box is a WAMP server while the live host is Linux. You have differences and they can bite you.
I am of the opposite opinion, and I see the above as a “sky is falling” scenario. The OS differences are negligible for the web-facing filesystem and database. Only the choice of web/db application and their versions will matter, and they are a minor issue at most for those who have their host manage the webserver and database applications. (This only applies to Linux hosting. I don’t accept clients who have Windows/IIS hosting.)
I also prefer that clients use WAMP.MAMP/etc rather than something like LocalFlywheel/Bitnami. It’s much easier for them to understand how to manage things in the background (SSH tunneling…lol), and migration to the location of their choice is a whole lot simpler.