How to deactivate all plugins when not able to access the administrative menus?
Sometimes it may be necessary to deactivate all plugins, but you can’t access the Administration Screens to do so. One of two methods are available to deactivate all plugins.

Use phpMyAdmin to deactivate all plugins.

In the table wp_options, under the option_name column (field) find the active_plugins row
Change the option_value field to: a:0:{}

Obviously, the article is written with the assumption it is being read by someone experience in phpMyAdmin, because there is absolutely no explanation on how to find the enumerated table.

I’ve spent 17 years in IT and it always amazes me how so many people author a “How To” article that assumes the reader knows the same things the author knows.