How can I monitor the progress of an import of a large .sql file?
If you're  just importing from a dump file from the CLI on *nix, e.g.

mysql -uxxx -pxxx dbname &lt; /sqlfile.sql


then first install pipe viewer on your OS then try something like this:

pv sqlfile.sql | mysql -uxxx -pxxxx dbname


which will show a progress bar as the program runs.  

It's very useful and you can also use it to get an estimate for mysqldump progress.

pv dumps the sqlfile.sql and passes them to mysql (because of the pipe operator). While it is dumping, it shows the progress. The cool thing is that mysql takes the data only as fast as it can progress it, so pv can show the progress of the import. I do not have any proof. But it seems so. I guess there is some buffer used, but at some point I think mysql does not read any more data when it is still busy processing.