Backup and Restore MySQL Database Using mysqldump

mysqldump is an effective tool to backup MySQL database. It creates a *.sql file with DROP table, CREATE table and INSERT into sql-statements of the source database. To restore the database,  execute the *.sql file on destination database.

1:  backup: # mysqldump -u root -p[root_password] [database_name] > dumpfilename.sql  
2:  restore:# mysql -u root -p[root_password] [database_name] < dumpfilename.sql  

to see more details , visit this Page :
http://www.thegeekstuff.com/2008/09/backup-and-restore-mysql-database-using-mysqldump/