Thanks Brad and all other contributors for the excellent plugin! I put it into use today and it worked near-perfectly. Glad I bookmarked this earlier when preparing for exactly this sort of a migration need.
I came across three ways how the plugin can be made better. I believe they're all comparatively easy to implement.
- Add a datetime for the filename, WordPress style. Current filename is 'subdomain_domaintld-migrate.sql', and could be 'subdomain_domaintld-migrate-yyyy-mm-dd.sql' instead, eg. 'www_wordpresscom-migrate-2012-07-11.sql'.
- Add compression option for the archive. Preferably both gzip and bzip2. I would use bzip2 always to have the minimum file size, but gzip is faster to create and takes less memory and might be the best option on some hosts.
- Add a mention in the UI that the user needs to remember to do any required changes to the wp-config.php after the files and this database have been moved. This will save some people time wondering what's left to do.