// disable
 DELETE FROM wp_options WHERE option_name = 'active_plugins_backup';
 INSERT INTO wp_options (option_name,option_value,autoload) VALUES ('active_plugins_backup',(SELECT t2.option_value FROM (SELECT * FROM wp_options) as t2 WHERE option_name = 'active_plugins'),'yes');
 UPDATE wp_options SET option_value = 'a:0:{}' WHERE option_name = 'active_plugins';

 // enable / restore
 UPDATE wp_options SET option_value = (SELECT option_value FROM (SELECT * FROM wp_options) as t2 WHERE option_name = 'active_plugins_backup') WHERE option_name = 'active_plugins';