How to import an SQL file using the command line in MySQL?

We always upload a a database in our sql through import. But when You import a huge/heavy size sql file then we need to used command.
It is very easy step :-
Try:

mysql -u username -p database_name < file.sql

A common use of mysqldump is for making a backup of an entire database:

shell> mysqldump db_name > backup-file.sql

You can load the dump file back into the server like this:

UNIX

shell> mysql db_name < backup-file.sql

The same in Windows command prompt:

mysql -p -u[user] [database] < backup-file.sql

PowerShell

C:\> cmd.exe /c "mysql -u root -p db_name < backup-file.sql"

MySQL command line

mysql> use db_name;
mysql> source backup-file.sql;