Working with XAMPP and and phpMyAdmin makes dealing with databases more visual, but importing large db dumb files can fail/take a long time.

Importing from the command line is faster and more stable.

Use the XAMPP mysql, if there is not a global mysql

cd /Applications/XAMPP/xamppfiles/bin 

Import

./mysql -u root -p db_name < ~/path/to/db/file.sql

• Importing a ca. 300MB file takes ca. 5 seconds.
• Make sure the DB "db_name" already exists.