I had to manually duplicate a server for development, and the only way I could duplicate the database was via SQL dump. I was importing into MySQL 14.14 on a virtual machine running Ubuntu 14. (Yeah, really old stuff, but the client isn't ready to allow an upgrade.)
The SQL dump came to about 6GB of non-compressed, plain ANSI text, so assuming that the import queries bloated the data with all the query instructions, character-escape sequences, and textual representations of binary data, the database ought to be smaller, right? I figured 6GB for the temporary SQL dump, plus 6GB for the database plus another 8GB for the rest of the system (20GB total) ought to be more than enough. It wasn't.
I rebuilt my virtual machine with a 30GB-disk thinking surely that would be enough, but it still wasn't. So I rebuilt my virtual machine with 50GB, and ended up with 16GB leftover when all was said and done. It turns out the database blew up to 20.5GB!
Somewhere along the way I figured out how to check the size of an existing database in MySQL, but what I would like to know, when the original database is not available to query, is there an application or MySQL command that can passively process a SQL dump without building the database, for the purpose of estimating the size of the resulting database?