Disable foreign key checks during import
The command 

SET FOREIGN_KEY_CHECKS=0;


sets the value of a variable in a session scope. So it affects on the current session only, and do not affect on another sessions, both already running and those that will be launched later.

If you specify new value as a global-scope one using the command

SET GLOBAL FOREIGN_KEY_CHECKS=0;


then the global setting will be set. It affects on the current session and sessions that will be launched later, and do not affects on another sessions, which are already running.

You can see it in practice. 


Start 2 CLI (mysql.exe) sessions. 
Check the variable value in all windows. 
Alter it in the 1st window. 
Start 3rd window. 
Check the variable value in all windows. 
Alter it globally in the 1st window. 
Start 4th window. 
Check the variable value in all windows.